pharmacology handout

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PHARMACOLOGY Pharmacology Study or science of drugs 3 Basic Areas of Pharmacology Pharmaceutics Pharmacokinetics Pharmacodynamics Pharmaceutics Study of how various dosage forms (e.g., injection, capsule, controlled release tablet) influence the way in which the body metabolizes a drug and the way in which the drug affects the body Pharmacokinetics Study of what the body does to the drug molecules Involves absorption, distribution, metabolism and excretion Pharmacodynamics Study of what the drug does to the body Involves drug-receptor interactions Receptor Theory Pharmacotherapeutics Focuses on the use of drugs and the clinical indications for administering drugs to prevent and treat diseases Defines the principles of drug actions (the cellular processes that change in response to the presence of drug molecules) Empirical therapeutics – drug therapy that is effective but for which the mechanism of action (MOA) is unknown Rational therapeutics – drug therapy in which specific evidence has been obtained for the mechanisms of drug action Toxicology Study of the adverse effects of drugs and other chemicals on living systems Toxic effects are often an extension of a drug’s therapeutic action Pharmacognosy Study of natural (vs synthetic) drug sources (both plants and animals) PHARMACOKINETICS Absorption Distribution Metabolism (biotransformation) Excretion A. Absorption Rate at which and extent to which a drug moves from its site of administration Factors affecting the rate and efficacy of absorption Route of administration Blood flow Surface area available Solubility of the drug Drug interactions pH (acidity (>uncharged) and alkalinity affects absorption) 1

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Page 1: Pharmacology Handout

PHARMACOLOGY

Pharmacology

Study or science of drugs

3 Basic Areas of Pharmacology

Pharmaceutics

Pharmacokinetics

Pharmacodynamics

Pharmaceutics

Study of how various dosage forms (e.g., injection, capsule, controlled release tablet) influence the way in which the body metabolizes a drug and the way in which the drug affects the body

Pharmacokinetics

Study of what the body does to the drug molecules

Involves absorption, distribution, metabolism and excretion

Pharmacodynamics

Study of what the drug does to the body

Involves drug-receptor interactions

Receptor Theory

Pharmacotherapeutics

Focuses on the use of drugs and the clinical indications for administering drugs to prevent and treat diseases

Defines the principles of drug actions (the cellular processes that change in response to the presence of drug molecules)

Empirical therapeutics – drug therapy that is effective but for which the mechanism of action (MOA) is unknown

Rational therapeutics – drug therapy in which specific evidence has been obtained for the mechanisms of drug action

Toxicology

Study of the adverse effects of drugs and other chemicals on living systems

Toxic effects are often an extension of a drug’s therapeutic action

Pharmacognosy

Study of natural (vs synthetic) drug sources (both plants and animals)

PHARMACOKINETICS

Absorption

Distribution

Metabolism (biotransformation)

Excretion

A. Absorption

Rate at which and extent to which a drug moves from its site of administration

Factors affecting the rate and efficacy of absorption

Route of administration

Blood flow

Surface area available

Solubility of the drug

Drug interactions

pH (acidity (>uncharged) and alkalinity affects absorption)

Bioavailability

The fraction or biologic fluid of the administered drug that gains access to its site of action

IV injected blood – 100%

NOT IV injected - < 100%

Factors affecting Bioavailability

First pass metabolism – biotransformation that occurs before the drug reaches its site of action (MC site - liver)

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All of the factors affecting absorption: pH, blood flow, drug interactions, route of administration

Routes of Drug Administration

Alimentary (Oral, Buccal, Sublingual, Rectal/Suppository)

Parenteral (Intravenous, intramuscular, subcutaneous, intrathecal)

Inhalation

Topical

Subcutaneous

Routes of Administration

Sublingual

Under the tongue

Nitroglycerin

Oral

The drug is swallowed and absorbed through the stomach and intestinal tract

Oral Glucose

Aspirin

Inhalation

a gas or aerosol inhaled by the patient

Oxygen by mask

Albuterol by hand-held metered- dose inhaler or by small-volume nebulizer

Injection

The drug is injected into a muscle mass

Epinephrine by auto-injector

Medication Forms

Tablets

compressed powder shaped into a disk

Aspirin

Nitroglycerin

Liquid for Injections

liquid with no particulate matter

Epinephrine

Medication Forms

Gel

viscous substance that the patient swallows

Oral Glucose

Suspension

drug particles mixed in a solute

Activated Charcoal

Fine powder for Inhalation

a crystalline solid mixed with liquid to form a suspension

Albuterol by hand-held metered-dose inhaler

Gas

Oxygen by mask

Spray

Nitroglycerin sub-lingual spray

Liquid/vaporized

Albuterol by small-volume nebulizer

B. Distribution

Process by which a drug leaves the bloodstream and enters the interstitium or the cells of the tissues

Passive diffusion, transport o special carrier proteins, active transport

C. Metabolism/ Biotransformation

Involves the biochemical alteration of a drug into an inactive metabolite, a more soluble compound or a more potent active metabolite

Liver, (cytochrome P450 enzymes) skeletal muscle, kidneys, lungs, plasma and intestinal mucosa

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D. Excretion

Process by which a drug or metabolite is removed from the body

Renal (MC), fecal, respiratory, breast milk, skin

Half life

The time required for half of an administered dose of drug to be eliminated by the body

aka elimination half-life

Steady state

Physiologic state in which the amount of drug removed via elimination is equal to the amount of drug absorbed with each dose

Onset of action

Time required for the drug to elicit a therapeutic response

Peak effect

Time required for a drug toto reach its maximum therapeutic response

Duration of action

Length of time that the drug concentration is sufficient (without more doses) to elicit a therapeutic response

Peak level – highest blood level

Trough level – lowest drug level

Enzyme

Substance that catalyzes biochemical reactions in a cell

Agonist

A drug that binds to and stimulates the activity of one or more biochemical receptor types in the body

Antagonist

A drug that binds to and inhibits the activity of one or more more biochemical receptor types in the body

Theurapeutic index

Ratio of a drug’s toxic level to the level that provides therapeutic benefits

Drug interaction

Alteration of the action of one drug by another

Synergistic effects

Occur when two drugs administered together interact in such a way that their combined effects are greater than the sum of the effects for each drug given alone

Antagonistic effects

Occur when the combination of two drugs results in drug effects that are less than the sum of the effects for each drug given separately

Rights of Medication Use

Right patientRight drugRight timeRight routeRight doseRight documentationRight assessmentRight educationRight evaluation Right to refuse

Effects

The desired result of administration of a medication

Side Effects

Effects that are not desired and that occur in addition to the desired therapeutic effects

Medication error

A preventable situation in which there is a compromise in the five rights of medication use

Adverse Drug Reaction (ADR)

Any reaction to a drug that is unexpected and undesirable and occurs at therapeutic drug dosages

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Allergic Reaction

Aka as hypersensitivity reaction

An immune response wherein various chemical mediators (histamine, cytokines, other inflammatory substances) are released

Immunoglobulins recognize the drug, its metabolite or another ingredient in a drug formulation as a dangerous foreign substance; they bind to the substance in an attempt to neutralize it

Can result in mild reactions (skin erythema or rashes) or to severe/ life threatening reactions (constriction of bronchial airways and tachycardia)

Idiosyncratic reaction

Not the result of a known pharmacologic property of a drug or of a patient allergy but instead occurs unexpectedly in a particular patient

Genetically determined abnormal response to normal dosages of a drug (ex, deficiency or excess of an enzyme)

Teratogenic effects – result in structural defects in the fetus

Mutagenic effects – permanent changes in the genetic composition of living organis; consist of alterations in chromosome structure, the number of chromosomes, or the genetic code of the DNA

Carcinogenic effects – cancer-causing effects of drugs, other chemicals, radiation and viruses

Indication

The reason for administering a medication or performing a treatment

Contraindication

A factor that prevents the use of a medication or treatment (eg. Allergies)

Dose

The amount of a drug to be administered at one time

Mechanism of Action

How a drug works

Medication Names

Chemical Namedescribes the drug’s chemical structureGeneric Name reflects the chemical name, but in shorter formTrade Namethe name the manufacturer uses to market the drugOfficial Namethe name used in the U.S. Pharmocopoeia

Steps in Administering Medication

Obtain an OrderConfirm OrderSteps in Administering MedicationSelect Proper MedicationAvoid contaminationCheck Expiration DateCheck For Signs of ContaminationDiscolorationCloudinessParticulate MatterVerify Form & Route Inform Patient of OrderInquire about allergiesRecheck Medication Expiration dateContaminationAt least two more times after initial checkAssess Patient prior to administration of the drugAdminister the correct dose by the correct routeDispose of Contaminated EquipmentReassess After Administration

COMMONLY USED ABBREVIATIONS

a.c.ante cibumbefore mealsp.c.post cibumafter mealsad. lib.ad libitumas desiredodomni dieonce a daybidbis in dietwice a daytid

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ter in diethree times a dayqidquarter in dieFour times a dayADLActivities of daily livinghshora somnihours of sleepODoculus dexterright eyeOSoculus sinisterleft eyeOUoculus uterqueboth eyeso.m.omni maneevery morningn.p.o.nulla per oremnothing by mouthq.h.quaque horaevery hourp.r.n.pro re nataas necessarystatstatimimmediately Systems of Measurement Common Household Measurement

1 quart = 4 cups1 pint = 2 cups1 cup =8ounces1 tbsp =3 tsp; 15 mlL1 tsp =60 gtts;5mL

Apothecary Measurements60 minims = 1 fluidram8 fluidrams = 1 fluid ounce

or 480 minims16 fluid ounces = 1 pint2 pints = 1 quart4 quarts = 1 gallon

Metric MeasurementsUnits of volume (liter)

1 mL = .001 L

1 dL = .1 L1 decaliter = 10 Liters

Units of weight (gram)1 mcg = .000001 gm1 mg = .001 gm1 cg = .01 gm1 dg = .1 gm

1 kilogram = 1000 gramsOther units

1 gm. = 15 gr.1 gr = 60 mg1 mg = 1,000 mcg

1 mL = 1 cc; 15 gtts; 1 gram60 mcgtts

1 L = 1 qt; 1000 mL1 gal = 4 L; 4 qt., 4000 mL1 ounce = 30 gm., 30 cc1 kg = 2.2 lbs1 lb = 16 ounces

REVIEW OF THE AUTONOMIC NERVOUS SYSTEM Nervous System

1.Central Nervous System

2. Peripheral Nervous System

Peripheral Nervous System

1.Somatic Nervous System (innervates skeletal muscle)

2.Autonomic Nervous System (ANS) – collection of nuclei, cell bodies, nerves, ganglia, and plexuses that provides afferent and efferent innervation to smooth muscle and visceral organs of the body; regulates functions that are not under conscious control BP, HR and intestinal motility)

Autonomic Nervous System (ANS)

1.Sympathetic Nervous System- originates in the thoracolumbar portion of the spinal cord

2.Parasympathetic Nervous System – originates from the cranial nerve nuclei III, VII, IX, X as well as the 3rd and 4th sacral spinal roots

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Sympathetic Nervous System

Flight or fight situationsHR increasesBP risesEyes dilateBlood sugar / glucoses risesBronchioles expandBlood flow shifts from the skin to skeletal muscles

Sympathetic Nervous System Receptors:Adrenergic Receptors- alpha 1

alpha 2 beta 1

beta 2Dopamine Receptors

Parasympathetic Nervous System Rest and digest systemSlows HRLowers BPIncreases intestinal activityConstricts pupilsEmpties urinary bladder

Receptors:Cholinergic receptors – muscurinic

nicotinic Neurotransmitters Major NT in the ANSAcetylcholine – cholinergic transmissionNorepinephrine – adrenergic transmission ANS drugs achieve their effects by acting as either agonists or antagonists at cholinergic and adrenegic receptors

DRUGS Cardiovascular Drugs Positive Inotropic DrugsAntidysrhythmic DrugsAntianginal DrugsAntihypertensive DrugsAntilipemic Drugs

Coagulation Modifier Drugs AnticoagulantsAntiplatelet drugsAntifibrinolytic drugs

Thrombolytic Drugs Drugs Affecting the Renal System Diuretic Drugs

Endocrine Drugs Thyroid and Antithyroid DrugsAntidiabetic DrugsAdrenal Drugs

Drugs Affecting Reproductive Functions

Respiratory Drugs Antihistamines, Decongestants, Antitussives and ExpectorantsBronchodilators and others

Antiinfective Drugs AntibioticsAntiviral DrugsAntitubercular DrugsAntifungal DrugsOthers

Antiinflammatory and Antirheumatic Drugs

GIT Drugs Acid-controlling DrugsAntidiarrheals and laxativesAntiemetics and Antinausea DrugsVitamins and Minerals/ Nutrition Supplements

Drugs affecting the CNS Analgesic DrugsGeneral and Local AnestheticsCNS Depressants and Muscle RelaxantsAntiepileptic DrugsAntiparkinsonian DrugsPsychotherapeutic DrugsCNS Stimulants and Related Drugs

Drugs Affecting the Autonomic System Adrenergic DrugsAdrenergic-Blocking DrugsCholinergic DrugsCholinergic-Blocking Drugs

Immunosuppressant and Antineoplastic Drugs

OTHERS: Hematologic, Dermatologic, Ophthalmic and Otic Drugs

Cardiovascular DrugsDrugs used to improve CV function include: Inotropic drugs

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Antiarrhtymic drugsAntianginal drugsAntihypertensive drugsDiureticsAntilipemic drugsInotropic drugs

Influence the contractility of muscular tissue (increase the force of heart’s contarction) – POSITIVE INOTROPIC

2 types:1. cardiac glycosides- slow the heart rate (negative chronotropic effect)- slow electrical impulse conduction (negative dromotropic effect)2. phosphodiesterase (PDE)

Cardiac GlycosidesGroup of drugs derived from digitalis ( foxglove plants)Digoxin – most common prototype of cardiac glycosides

Pharmacokinetics:Capsules are absorbed most efficientlyFollowed by elixir then tabletsPoorly bound to plasma proteinsMost of the drugs is excreted by the kidneys unchanged

Pharmacodynamics:It boosts intracellular clacium at the cell membraneEnhance the movement of calcium into the myocardial cells and stimulate the release, or block the reuptake, of norepinephrine at the adrenergic nerve terminalActs on CNS

Pharmacotherapeutics:Heart failure, supraventricular arrhtymias, paroxysmal atrial tachycardia

Assessment:1. Obtain Hx 2. Monitor drug effectiveness – take apical

pulse for 1 minute before each dose3. Monitor digoxin levels (therapeutic blood

levels- 0.5 to 2 ng/ml)4. Obtain blood for digoxin levels 8 hours

after the last dose by mouth5. Closely monitor K levels Intervention:1. Before giving a loading dose, obtain a

baseline

2. Take the apical pulse before giving this meds

3. Wihthold the drug and notify the prescriber if the pulse rate slows to 60 bpm or less

4. Infuse the IV form slowly over at least 5 minutes

PDE InhibitorsTypically used for short term-term management of heart failure or long term management in patients awaiting heart transplant surgeryExamples:Inamrinone Milrinone

Warning:- when giving PDE inhibitors (milrinone), remember that improvement of cardiac output may result in enhanced UO. Expect a dosage reduction in diuretic therapy as heart failure improves- potassium loss may predispose the patient to

Digoxin toxicity

Antianginal Reducing myocardial oxygen demand (reducing the amount of oxygen the heart needs to do its work)Or by increasing the supply of oxygen to the heart

Three classes:Nitrates (acute angina)Beta-adrenergic blockers (long-term prevention of angina)Calcium channel blockers (used when other drugs fails)

Nitrates Commonly prescribed:Amyl nitriteIsosorbide dinitrateIsosorbide mononitrateNitroglycerin

Assessment:Monitor VS – IV nitroglycerin (monitor BP and PR q 5 to 15 minutes while adjusting the dose and every hour thereafter)Monitor the effectiveness of prescribed drugsObserve for adverse reactions

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Interventions:Maybe given on empty stomach, either 30 minutes before or 1 to 2 hours after meals (tell to swallow not chew)Have the patient sit or lie down when receiving the first nitrate dose (take pulse/BP before giving the dose)Don’t give beta-adrenergic blocker or calciul channel blocker to relieve anginaWihthold if heart rate < 60bpmDilute IV nitro with D5W or NSS for injection (avoid IV filters because it binds to plasticSublingual nitro can be repeated every 10 to 15 minutes up to 3 dosePlace topical ointments on paper as prescribed; place the paper on a nonhairy area and cover it with plasticRemove a transdermal patch before defibrillation (aluminum back may be explode)Be aware that the drug may initially cause headache until tolerance develops or the dose is minimized

Antihypertensive drugsUsed to treat hypertensionClasses:Angiotensin-converting enzyme (ACE) inhibitorsAngiotensin-receptor blockersBeta-adrenergic antagonistCalcium channel blockerDiuretics

ACE inhibitorReduce BP by interrupting the renin-angiotensin activating system (RAAS)Commonly used:CaptoprilEnalaprilLisinoprilRamiprilAssessment:Obtain a baseline BP and pulse rate and rhythmMonitor adverse reactions (headache, fatigue, dry non-productive cough, angioedema, tickling in the throat)Monitor monitor weight, fluid and electrolyte statusMonitor a transdermal patch for dermatitisIntervention:If orally, administer before mealsAssist the patient to get up slowly to prevent orthostatic hypotensionSodium restriction, calorie reduction, stress mngt, exercise program should be maintainPeriodic eye examinations are recommended

Angiotensin II receptor blocking agents Lower BP by blocking the vasoconstrictive effects of angiotension IICommonly used:LosartanValsartanIrbesartantelmisartan Assessment:Obtain baseline VSWeight, fluid and electrolytes statusCompliance and treatmentTolerance and therapeutic effectsDermatitisAdverse reactionsInterventions:If orally administer the drug with food or at bedtimeIf giving once daily, administer in the morning to prevent insomia

Beta-adrenergic blockersAlso used for long term prevention of anginaCommonly used:AtenololBisoprololCarvedilolNadololPindolol

Calcium channel blockersAlso used to treat arrhythmias and to prevent anginaCommonly used:Amlodipine Nifedipine verapamil

Sympatholytic drugsReduce blood pressure by inhibiting or blocking the SNSClassified by their site or mechanism of action and include:Central-acting SNS inhibitors – clonidine Hcl, methyldopaAlpha adrenergic blockers – prazosin, terazosin Mixed alpha and beta-adrenergic blockers – carvedilol, labetalol Norepinephrine depletors – reserpine

Direct vasodilatorsDecrease systolic and diastolic BPThey act on arteries, veins or both

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Examples:Diaxozide Hydralazine Nitroprusside

Renal PharmacologyDrugs affecting the KidneyOutline of reviewRecall the anatomy of the urinary systemRecall the physiology of the urinary systemReview- drugs of the following categories:1. Diuretics2. Drug for BPH

DiureticsAgents that increase the amount of urine produced by the kidneys

Classes of DiureticsFive major classes1. Thiazides and thiazide-like2. Loop diuretics3. Potassium-sparing 4. Carbonic anhydrase inhibitors5. Osmotic diuretics

General indications for the use of the diureticsTreatment of edemaUrine output will increase and excess fluid is flushed out of the body

Treatment of CHFThe sodium loss in the kidney is associated with water loss

Treatment of HypertensionDiuretics will decrease the blood volume and serum sodium

Treatment of GlaucomaDiuretics will provide osmotic pull to remove some of the fluid from the eye to decrease the IOP

time of administration of the diureticsUsually in the morning!!

Diuretics ComparisonThiazidesPrototype: Hydrochlorothiazide 1. Bendroflumethiazide 2. Benthiazide 3. Chlorothiazide (Diuril)4. Hydroflumethiazide 5. Methylclothiazide

6. Trichlormethiazide

Thiazide-like1. Indapamide2. Quinethazone3. Metolazone4. Chlorthalidone

ThiazidesPharmacodynamicsThese drugs BLOCK the chloride pumpThis will keep the Chloride and Sodium in the distal tubule to be excreted into the urine Potassium is also flushed out!!

Special Pharmacodynamics: Side effectsHypokalemiaDECREASED calcium excretionà hypercalcemiaDECREASED uric acid secretionà hyperuricemiaHyperglycemia

Loop DiureticsPrototype: Furosemide 1. Bumetanide 2. Ethacrynic acid3. Torsemide

Pharmacodynamics High-ceiling diureticsBLOCK the chloride pump in the ascending loop of Henle SODIUM and CHLORIDE reabsorption is preventedPotassium is also excreted together with Na and Cl

Special Pharmacodynamics: side-effectsHypokalemiaBicarbonate is lost in the urineINCREASED calcium excretionà HypocalcemiaOtotoxicity- due to the electrolyte imbalances

Potassium sparing diureticsPrototype: Spironolactone 1. Amiloride 2. Triamterene

Potassium sparing diureticsPharmacodynamics Spironolactone is an ALDOSTERONE antagonistTriamterene and Amiloride BLOCK the potassium secretion in the distal tubuleDiuretic effect is achieved by the sodium loss to offset potassium retention

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Potassium sparing diureticsPharmacokinetics: Side effectsHYPERkalemia!Avoid high potassium foods:BananasPotatoesSpinachBroccoliNutsPrunesTomatoesOrangesPeaches

Osmotic DiureticsPrototype: Mannitol 1. Glycerin2. Isosorbide 3. Urea

Osmotic DiureticsPharmacodynamicsMannitol is a sugar not well absorbed in the nephronà osmotic pull of waterà diuresis

Pharmacokinetics: side effectsSudden hypovolemia Important for the nurse to warm the solution to allow the crystals to DISSOLVE in the bottle!

Carbonic Anhydrase InhibitorsPrototype: Acetazolamide 1. Methazolamide Carbonic Anhydrase InhibitorsPharmacodynamicsCarbonic Anhydrase forms sodium bicarbonateBLOCK of the enzyme results to slow movement of hydrogen and bicarbonate into the tubulesplus sodium is lost in the urinePharmacokinetics: side effectsMetabolic ACIDOSIS happens when bicarbonate is lostHypokalemia

The Nursing Process and the diureticsASSESSMENTAssess the REASON why the drug is given:ASSESSMENTThe nurse must elicit history of allergy to the drugs

Allergy to sulfonamides may contraindicate the use of thiazides Assess fluid and electrolyte balanceAssess other conditions like gout, diabetes, pregnancy and lactation

ASSESSMENTPhysical assessmentVital signsSpecial electrolyte and laboratory examinationAssess symptom of body weakness which may indicate hypokalemia

Nursing DiagnosisFluid volume deficit related to diuretic effectAlteration in urinary patternPotential for injury (ototoxocity, hypotension)Knowledge deficit

IMPLEMENTATIONAdminister IV drug slowlySafety precaution for dizziness/hypotensionProvide potassium RICH foods for most diuretics, with the exception of spironolactone Provide skin care, oral care and urinary care

IMPLEMENTATIONMonitor DAILY WEIGHT- to evaluate the effectiveness of the therapy Monitor urine output, cardiac rhythm. Serum electrolytesADMINISTER in the MORNING!Administer with FOOD!

EVALUATION: for effectiveness of therapyWeight lossIncreased urine outputResolution of edemaDecreased congestionNormal BP

Pharmacology of the Selected Endocrine DrugsEndocrine MedicationsThyroid Medications

Thyroid hormonesThese products are used to treat the manifestations of hypothyroidismReplace hormonal deficit in the treatment of

HYPOTHYROIDSMFatigueWeight gainCold intolerance

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Irregular MensesMyxedema

ANTI-THYROID medications1. Methimazole (Tapazole)2. PTU (prophylthiouracil)3. Iodine solution- SSKI and Lugol’s solution

ANTI-THYROID medications: Indications (hyperthyroidism)

1. Grave’s disease 2. Thyrotoxicosis

Hyperthyroidism Hypersensitivity to heatWeight loss despite increased appetiteNervousness (palpitation)Sweating

ANTI-THYROID medications:Absorption is good orally

Side-effects of thionamides N/V, drowsiness, lethargy, bradycardia, skin rashGI complaintsArthralgia, myalgia AGRANULOCYTOSISMost important to monitor

Side-effects of Iodine solutions Lugol’sMost common adverse effects is HYPOTHYROIDISMIodism= metallic taste, burning in the mouth, sore teeth and gums, diarrhea, stomach upset

Nursing responsibilities1. Monitor VS, T3 and T4, weight2. The medications WITH MEALS to avoid gastric upset3. Instruct to report SORE THROAT or unexplained FEVER4. Monitor for signs of hypothyroidism. Instruct not to stop abrupt medicationLugol’s SolutionUsed to decrease the vascularity and size of the thyroid (in preparation for thyroid surgery) T3 and T4 production diminishesGiven per orem, can be diluted with juice, administered WITH foodsUse straw to decrease stainingMonitor iodism

Thyroid Storm Surgery, stress or illness

Endocrine MedicationsAnti-diuretic hormonesEnhance re-absorption of water in the kidneysIncreases water permeability in the renal collecting ductsAlso stimulates VASOCONSTRICTION and increases the blood pressure

Therapeutic Indications1. Hormonal replacement2. Used in diagnostic procedure3. Used to control the hemorrhage in

variceal bleeding 4. Treatment of enuresis

Used in DI1. Desmopressin and Lypressin intranasally2. Pitressin IntraMuscularlyEndocrine MedicationsAnti-diuretic hormones

SIDE-effectsFlushing and headacheWater intoxicationCVS: heart block, MIRenal: hyponatremiaGangrene due to vasoconstriction DM Drug therapy

DRUG THERAPY and MANAGEMENTUsually, this type of management is employed if diet modification and exercise cannot control the blood glucose level.

These agents are employed to control the blood glucose levelThey can be insulin and oral agentsThese are given to replace the hormone in the bodyIf hormone is still present BUT decreased, Oral agents are given

Diabetes MellitusDRUG THERAPY and MANAGEMENTBecause the patient with TYPE 1 DM cannot produce insulin, exogenous insulin must be administered for life.

TYPE 2 DM may have decreased insulin production, ORAL agents that stimulate insulin production are usually employed.

PHARMACOLOGIC INSULIN

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This may be grouped into several categories according to:

1. Source- Human, pig, or cow2. Onset of action- Rapid-acting, short-

acting, intermediate-acting, long-acting and very long acting

PHARMACOLOGIC INSULINThis may be grouped into several categories according to:

3. Pure or mixed concentration4. Manufacturer of drug

Diabetes MellitusGENERALITIES1. Human insulin preparations have a shorter duration of action than animal sourceDiabetes Mellitus2. Animal sources of insulin have animal proteins that may trigger allergic reaction and they may stimulate antibody production that may bind the insulin, slowing the action 3. ONLY Regular insulin can be used INTRAVENOUSLY!Diabetes Mellitus4. Insulin are measured in INTERNATIONAL UNITS or “iu”5. There is a specified insulin injection calibrated in unitsMixed insulin are also availableThe most common of which is the 70-30 insulinMade up of :70% NPH and 30% regular insulin in the vial

Comparison of Insulin Peak actionDiabetes MellitusRAPID ACTING INSULINLispro (Humalog) and Insulin Aspart (Novolog)Produces a more rapid effect and with a shorter duration than any other insulin preparation

RAPID ACTING INSULINONSET- 5-15 minutesPEAK- 1 hourDURATION- 3 hoursInstruct patient to eat within 5 to 15 minutes after injection

REGULAR INSULINAlso called Short-acting insulin“R”Usually Clear solution administered 30 minutes before a mealDiabetes Mellitus

REGULAR INSULINONSET- 30 minutes to 1 hourPEAK- 2 to 4 hoursDURATION- 4 to 6 hours

INTERMEDIATE ACTING INSULINCalled “NPH” or “LENTE”Appears white and cloudy

INTERMEDIATE ACTING INSULINONSET- 2-4 hoursPEAK- 4 to 6-12 hoursDURATION- 16-20 hours

LONG- ACTING INSULIN“UltraLENTE”Referred to as “peakless” insulinLONG- ACTING INSULINONSET- 6-8 hoursPEAK- 12-16 hoursDURATION- 20-30 hours

HEALTH TEACHINGRegarding Insulin SELF- Administration1. Insulin is administered at home subcutaneouslyDiabetes Mellitus2. Cloudy insulin should be thoroughly mixed by gently inverting the vial or ROLLING between the hands3. Insulin NOT IN USE should be stored in the refrigerator, BUT avoid freezing/extreme temperature4. Insulin IN USE should be kept at room temperature to reduce local irritation at the injection site5. INSULIN may be kept at room temperature up to 1 month6. Select syringes that match the insulin concentration.U-100 means 100 units per mL7. Instruct the client to draw up the REGULAR (clear) Insulin FIRST before drawing the intermediate acting (cloudy) insulin8. Pre-filled syringes can be prepared and should be kept in the refrigerator with the needle in the UPRIGHT position to avoid clogging the needle9. The four main areas for insulin injection are- ABDOMEN, UPPER ARMS, THIGHS and HIPSInsulin is absorbed fastest in the abdomen and slowest in the hipsInstruct the client to rotate the areas of injection, but exhaust all available sites in one area first before moving into another area.10. Alcohol may not be used to cleanse the skin

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11. Utilize the subcutaneous injection technique- commonly, a 45-90 degree angle. 12. No need to instruct for aspirating the needle13. Properly discard the syringe after use.

T-I-ETest bloodà Inject insulin à Eat food

ORAL HYPOGLYCEMIC AGENTSThese may be effective when used in TYPE 2 DM that cannot be treated with diet and exerciseThese are NEVER used in pregnancy!

ORAL HYPOGLYCEMIC AGENTSThere are several agents:SulfonylureasBiguanidesAlpha-glucosidase inhibitorsThiazolidinedionesMeglitinides

These drugs are given per orem and are effective only in type 2 DMCommon adverse effects include:HypoglycemiaDiarrhea, jaundice, nausea and heartburnAnemia , photosensitivity

General Nursing Consideration1. Observe for manifestations of

hypoglycemia2. Assess for allergic reaction3. Instruct to take the medication at the

same time each day4. Caution to avoid taking other drugs

without consultation with physician5. THESE medications SHOULD NEVER be given to pregnant women, so rule out pregnancy6. Instruct to wear sunscreen7. Advise to bring simple sugar to be taken when hypoglycemic episodes occur

SULFONYLUREASMOA- stimulates the beta cells of the pancreas to secrete insulinClassified as to generations- first and second generations

FIRST GENERATION- Acetoheximide, Chlorpropamide, Tolazamide and TolbutamideSECOND GENERATION- Glipizide, Glyburide, Glibenclamide, GlimepirideDiabetes Mellitus: Sulfonylureas

The most common side –effects of these medications are Gastro-intestinal upset and dermatologic reactions.HYPOGLYCEMIA is also a very important side-effectGiven 30 minutes before meals- breakfast

Diabetes Mellitus: SulfonylureasChlorpropamide has a very long duration of action. This also produces a disulfiram-like reaction when taken with alcoholSecond generation drugs have shorter duration with metabolism in the kidney and liver and are the choice for elderly patients

BIGUANIDESMOA- Facilitate the action of insulin on the peripheral receptorsThese can only be used in the presence of insulin

BIGUANIDES= “formin”They have no effect on the beta cells of the pancreas Metformin (Glucophage) and Phenformin are examplesThe most important side effect is LACTIC ACIDOSIS!These are not given to patient with renal impairmentThese drugs are usually given with a sulfonylurea to enhance the glucose-lowering effect more than the use of each drug individually

ALPHA-GLUCOSIDASE INHIBITORSMOA- Delay the absorption of glucose in the GIT Result is a lower post-prandial blood glucose levelThey do not affect insulin secretion or action!Side-effect: DIARRHEA and FLATULENCEExamples of AGI are Acarbose and MiglitolThey are not absorbed systemically and are very safeThey can be used alone or in combination with other OHASide-effect if used with other drug is HYPOGLYCEMIANote that sucrose absorption is impaired and IV glucose is the therapy for the hypoglycemia

THIAZOLIDINEDIONESMOA- Enhance insulin action at the receptor siteThey do not stimulate insulin secretionExamples- Rosiglitazone, PioglitazoneThese drugs affect LIVER FUNCTION

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Can cause resumption of OVULATION in peri-menopausal anovulatory women

MEGLITINIDESMOA- Stimulate the secretion of insulin by the beta cellsExamples- Repaglinide and NateglinideDiabetes Mellitus

MEGLITINIDESThey have a shorter duration and fast actionShould be taken BEFORE meals to stimulate the release of insulin from the pancreasDiabetes MellitusMEGLITINIDESPrincipal side-effect of meglitinides- hypoglycemiaCan be used alone or in combinationReproductive HormonesGonadal hormones include agents that affect the female and male reproductive cycleFemale hormones include ESTROGENS, PROGESTINS and ovarian hormonesMale hormones include ANDROGENS and anabolic steroidsReproductive HormonesThe GENERAL Mechanism of ActionThese hormones interfere with the normal cycle of hormone balanceReproductive HormonesINDICATIONS

1. FEMALE: Hormonal replacement therapy, oral contraception, treatment of infertility and management of some tumors

2. MALE: replacement therapy, metabolic stimulators and treatment of some tumors

Reproductive HormonesEstrogensConjugated estrogenEstradiolEthinyl estradiolDiethylstilbesterol (DES)ClomipheneReproductive HormonesProgestinsMedroxyprogesterone acetate (Provera)MegestrolNorethindroneLevonorgestrel (Norplant)NorgestrelNorethindrone acetateReproductive HormonesAndrogensTestosterone cypionate

MethyltestosteroneFluoxymesteroneAqueous testosteroneReproductive HormonesOral Contraceptive PillsTwo types are available: Combination estrogen and progesterone AND progestins onlyReproductive HormonesOral Contraceptive Pills: DYNAMICSInhibits OVULATION by altering the hypothalamus and gonadotropin axisAlters the MUCUS to prevent sperm entryAlters the uterine endometrium to prevent implantation Suppresses the ovariesReproductive HormonesOral Contraceptive Pills: IndicatorsSuppression of ovulation for prevention of pregnancyRegulation of menstrual cycle and management of dysfunctional bleeding Treatment of endometriosisReproductive HormonesOral Contraceptive Pills: KineticsEasily absorbed orallyNORPLANT provides 5 years of contraception Provera provides 3 months of protectionMetabolized and excreted in liverReproductive HormonesOral Contraceptive Pills:Not to be used in patients with history of, hypertension, thromboemoblic or CVA diseaseNot given in certain cancersContraindicated in pregnancySMOKING should be avoided when under therapyReproductive HormonesOral Contraceptive Pills: Drug InteractionRifampicin, penicillin and tetracycline REDUCE effectiveness of contraceptionBenzodiazepines decrease the levels of OCP Reproductive HormonesOral Contraceptive Pills:Side effectsCNS: headacheCV: Thromboembolic disease, MI, hypertension and pulmonary edemaNAUSEA and cholestatic JAUNDICEBreast tenderness, weight gain, edema, breakthrough bleeding, acne Reproductive hormonesNursing Considerations

1. Assess for risk factors and the ability to comply with medications

2. Determine the type of OCP used

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Monophasic pills provide constant dosing of BOTH estrogen and progestinBiphasic pills provide constant estrogen but varying progestin dosesTriphasic pills provide varying Estrogen and ProgesteroneReproductive hormonesNursing Considerations3. Teach the common side-effects and re-assure that these will decrease in time4. Instruct to use other means of contraception if antibiotics and anticonvulsants are also taken5. WARN the client to avoid smoking because this will increase the risk for embolic episodes ClomipheneA synthetic, non-steroidal estrogen Increases the secretion of gonadotropins and initiates the secretion of FSH and LHOVULATION will occurUsed in the treatment of infertilityReadily absorbed orally ClomipheneSide effects can be:Risk for Multiple pregnancyNausea, breast discomfort, headache and GI disturbancesVisual disturbancesEnlargement of the ovariesViagra (Sildenafil)A medication used for penile erectile dysfunctionSelectively inhibits receptors and enzyme Phosphodiesterase EThis increases the nitrous oxide levels allowing blood flow into the corpus cavernosum Viagra (Sildenafil)Contraindicated in patients with bleeding disorders and with penile implantsCaution: Coronary Artery Disease and concomitant use of nitratesSide-effects: PRIAPISM, headache, flushing, dyspepsia, UTI, diarrhea and dizziness Viagra (Sildenafil)Nursing considerationAssess for risk factorsInstruct to take the drug ONE hour before sexual actDrug is taken orallyPharmacology of Respiratory DrugsDrugs Affecting the Respiratory SystemAntihistamines- are used to block the release or action of histamine- a chemical mediator of inflammation that increases secretions and constricts the air passageway

Antitussives- agents utilized to block the cough reflexDrugs for COPD (chronic obstructive pulmonary disease)- which includes the Bronchodilators, inhaled steroids, Leukotriene receptor blockers and other anti-asthma drugsDecongestants- are utilized to decrease the blood flow to the upper respiratory tract and decrease the excessive production of secretionsExpectorants- are used to decrease the viscosity of sputum to effectively increase productive cough to clear the airwaysThe ANTIHISTAMINESAlso called H1 blockers or H1 antagonists, these are agents designed to relieve respiratory symptoms and to treat allergic conditions.The ANTIHISTAMINESThe anti-histamines are group according to the “generation”. The FIRST GENERATION agents have greater anticholinergic effects and can cause more sedation and drowsiness! These agents cause drowsiness. The SECOND GENERATION agents have fewer anticholinergic effects that is why they cause less sedation. The ANTIHISTAMINESThe FIRST GENERATION ANTIHISTAMINES1. Azatadine 11. Dimenhydrinate 2. Azelastine 12. Diphenhydramine 3. Brompheniramine 13. Hydroxyzine 4. Buclizine 14. Meclizine 5. Cetirizine 15. Methdilazine 6. Chlorpheniramine 16. Promethazine 7. Clemastine 17. Tripelenamine 8. Cyclizine 18. Carbinoxamine9. Cyproheptadine 19. Trimeprazine 10. Dexchlorpheniramine 20. Triprolidine The ANTIHISTAMINESThe SECOND GENERATION ANTIHISTAMINESFexofenadineLoratidineAzelastineCetirizineAnti-HistamineThe Mechanism of Action

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These agents SELECTIVELY block the effects of histamine at the HISTAMINE-1 receptor sites in the target tissue by competing with histamine for receptor, decreasing the cellular responses They also have antipruritic property.Anti-HistamineClinical Indications for Use in respiratory system

1. rhinitis2. allergic sinusitis3. uncomplicated urticaria

Anti-HistamineContraindications and Precautions for the use of the antihistaminesPregnancy and lactation are contraindications, and they agents are used cautiously in patient with impaired liver and kidney functions. Fatal arrhythmiasAnti-HistaminePharmacodynamics: Drug effects on the body

1. CNS- drowsiness and sedation, most pronounced if first generation agents are used

2. Fatigue, dizziness and disturbed coordination.

3. Anticholinergic effects= drying of the respiratory mucus membrane, GI upset and nausea, arrhythmias, dysuria, urinary retention

4. Skin dryness Anti-HistamineImplementationThe nurse should administer the drug on an EMPTY stomach, or 1 hour before or 2 hours after meals to increase the absorption. Give with food if GI upset occurs Offer sugarless lozenges or hard candy to counteract dryness of the mouth. Give frequent oral careProvide safety measures if drowsiness may occur. Side rails up, assist in ambulation, and advise not to drive or operate dangerous machineries or delicate tasks. Anti-HistamineNursing implementationIncrease humidity in the room by utilizing nebulizers and provide adequate hydrationAllow the patient to void first before administering the drug. Caution the patient against use of OTC drugs, alcoholic beverages and sedatives because they may cause extreme sedation.Anti-HistamineEvaluation

Monitor patient’s response to the drug, the adverse effects and the effectiveness of comfort measures employedDecreased allergic symptomsDecreased occurrence of rhinitisAnti tussivesThese are agents suppress the cough reflex on the MEDULLA oblongata to suppress cough of many respiratory conditions. The anti-tussives are the following:Benzonatate= narcotic anti-tussiveButamirate citrate= non-narcoticCodeine= narcoticDextromethorphan= non-narcoticHydrocodone= narcoticAnti tussivesPharmacodynamics: Therapeutic use of the antitussivesThe traditional antitussives act directly on the MEDULLARY cough of the brain to depress the cough reflex, but it does NOT suppress respiration.Dextromethorphan DOES not depress respiration. AntitussivesClinical Use of the antitussive: utilized for the treatment of coughContraindications and Indications for use of antitussivesThese agents are NOT given to patients who have undergone thoracic surgeries because they need to cough to maintain airway patency. Precautions are instituted when giving to patients with asthma, emphysema or COPD because an accumulation of secretions may occur. Anti tussives

Pharmacodynamics: Drug Effects

Respiratory- dryness of mucosal membranes, increased viscosity of secretions

CNS- drowsiness, dizziness and sedation

GIT- nausea, constipation and dry mouth, GIT upset

Nursing Process and the antitussives

Anti tussives

Implementation

Emphasize that the drug should be taken only on a specified time frame as ordered

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Provide other measures to relieve cough like provide humidified oxygen, cool temperatures, fluids and use of lozenges

Provide health teaching as to drug name, dosage and measures to handle side-effects

Caution that alcohol, narcotics, sedatives-hypnotics can cause CNS depression when used with antitussives.

Mucolytics

These are agents that breakdown mucous in order to help respiratory patients in coughing up thick, tenacious secretions.

The following are the mucolytics:

Acetylcysteine

Dornase alfa

Mucolytics

Pharmacodynamics: Mechanism of Action

These agents work in the following ways: acetylcysteine affects the mucoproteins in the respiratory secretions by splitting apart disulfide bonds that are responsible for holding the mucus materials together.

Mucolytics

Cautions should be used in cases of acute bronchospasms, peptic ulcer and esophageal varices.

The increased secretions can aggravate the problem

Indications for use

COPD

Pneumonia

Tuberculosis

Atelectasis

Mucolytics

Pharmacodynamics: drug effects

GIT= GI upset, stomatitis, irritation of the respiratory tract

others: Bronchospasm and rash

Mucolytics

Implementation

Instruct the patient to avoid combining with other drugs in the nebulizer to avoid formation of precipitates

The dug can be administered via nebulizers with the drug diluted with sterile water.

Remind the patient that the drug may irritate the respiratory mucosa

Provide through patient teaching including drug name and prescribed dosage

Have suction machine available

Drugs for COPD

The agents used for COPD may be one of the following:

Bronchodilators such as adrenergics and the xanthines used to assist in opening the narrowed airways

Steroids are used to decrease inflammation

Leukotriene modifiers reduce inflammation in the lung tissue

Cromolyn sodium and nedocromil act as anti-inflammatory agents by suppressing the release of HISTAMINE from the mast cells

Expectorants are used to assist in loosening secretions from the airways

Antibiotics are prescribed to prevent serious complications from bacterial infections.

The BRONCHODILATORS

These are Bronchodilators medication used to facilitate respiration by dilating the airways.

They are helpful in symptomatic relief or prevention of bronchial asthma and bronchospasm associated with COPD.

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The BRONCHODILATORS

The bronchodilators are:

Xanthines

Sympathomimetics (beta-agonists)

Anticholinergics

Inhaled steroids

The XANTHINES

Xanthines, including caffeine and theophylline, come from a variety of naturally occurring sources. These drugs were once main choice for treatment of asthma and bronchospasm.

The Xanthines include:

Aminophyline

Caffeine

Dyphilline

Oxytriphylline

Pentoxyfilline

Theophylline

The XANTHINES

Pharmacodynamics: Drug action

The xanthines have a direct effect on the smooth – muscles of the respiratory tract, both those on the bronchi and the blood vessels.

The xanthines stimulate the CNS such that respiration is stimulated, coronary arteries dilate and pulmonary arteries dilate, with additional effect of diuresis.

The XANTHINES

Clinical Use of the xanthines

Xanthines are indicated for the symptomatic relief or prevention of bronchial asthma and reversal of bronchospasm associated with COPD.

Unlabeled uses include stimulation of respiration in Cheyne – Stokes respiration and

the treatment of apnea and bradycardia in premature infants.

The XANTHINES

Pharmacodynamics: drug effects

GI upset, anorexia, vomiting, gastric pain, nausea, irritability, and tachycardia to seizures, brain damage, and even death.

Theophylline toxicity occurs when concentration is above 20 ug/mL.

Rapid IV administration of aminophylline can cause dizziness, flushing, severe HYPOTENSION, bradycardia and palpitations.

The XANTHINES

Implementation

Monitor vital signs and note for the BP and HR because there may be Hypotension and tachycardia.

Administer oral drug with food to relieve GI irritation, if GI upset is a problem.

Monitor patient response to the drug= relief of respiratory difficulty and improved airflow, to determine the effectiveness of the drug dosage and to adjust dosage as needed.

The XANTHINES

Implementation

Provide comfort measures, including rest periods, quiet environment, dietary control of caffeine, and headache therapy as needed, to help the patient cope with the effects of drug therapy.

Provide adequate hydration

Don’t crush enteric coated and sustained release tablets

Encourage to stop smoking

The XANTHINES

Evaluation

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Monitor patient response to the drug (improved air flow, ease of respirations).

Monitor for adverse effects (CNS effects, cardiac arrhythmias, GI upset, local irritation)

The SYMPATHOMIMETICS

These are drugs that mimic the effects of the sympathetic nervous system.

One of the actions of the sympathetic nervous system is dilation of the bronchi and increased rate and depth of respiration.

This is the desired effect when selecting a sympathomimetic as a bronchodilator.

The SYMPATHOMIMETICS

Sympathomimetics that are used as bronchodilators include the following:

Albuterol

Bitolterol

Isoproterenol

Metaproterenol

Salbutamol

Terbutaline

Ephedrine

Epinephrine= the drug of choice for the treatment of acute bronchospasm, including that which is caused by anaphylaxis

The SYMPATHOMIMETICS

Clinical Use

Asthma and other Allergic conditions

bronchospasm in reversible obstructive airway disease, such as acute and chronic asthma and chronic bronchitis.

They have also been effective in preventing exercise-induced bronchospasm.

Used also in Preterm labor

The SYMPATHOMIMETICS

CONTRAINDICATIONS/CAUTIONS

These drugs are contraindicated or should be used with caution, depending on the severity of the under- lying condition, in conditions that would be aggravated by the sympathetic stimulation.

Such conditions include cardiac disease, vascular disease, arrhythmias, diabetes, hyperthyroidism, pregnancy, and lactation.

The SYMPATHOMIMETICS

Pharmacodynamics: drug EFFECTS

Adverse effects of these drugs, which can be attributed to sympathomimetic stimulation include

CNS stimulation= tremors, headache, nervousness

GI- GI upset

Cardio= cardiac arrhythmias, hypertension, tachycardia and palpitations, vasoconstriction

Respi= bronchospasm, sweating, pallor, and flushing.

Hyperglycemia, Urinary retention

The SYMPATHOMIMETICS

Implementation

Assure the patient that the drug of choice will vary with each individual. These sympathomimetics are slightly different chemicals and are prepared in a variety of delivery systems.

Advise patients to use the minimal amount needed for the shortest period of time necessary, to prevent adverse effects and accumulation of drug levels.

The SYMPATHOMIMETICS

Implementation

Instruct the patient on how to use the inhalers. Teach patients who use one of these drugs for exercise-induced asthma to use it 30 to 60 minutes before exercising to ensure peak therapeutic effects when they are needed.

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Provide safety measures as needed if CNS effects become a problem, to prevent patient injury.

The SYMPATHOMIMETICS

Implementation

Provide small, frequent meals and nutritional consultation if GI effects interfere with eating to ensure, proper nutrition.

Carefully teach the patient about the proper use of the prescribed delivery system.

Review that procedure periodically as improper use may result in ineffective therapy.

The SYMPATHOMIMETICS

Evaluation

Monitor patient response to the drug (improved breathing).

Monitor for adverse effects (CNS effects, increased pulse and blood pressure, GI upset)

INHALED STEROIDS

Inhaled steroids have been found to be a very effective treatment for bronchospasm.

Agents include

Beclomethasone = given via MDI inhaler

Flunisolide

Triamcinolone

Dexamethasone= is given IV and orally, not inhaled

Prednisone and prednisolone

INHALED STEROIDS

THERAPEUTIC ACTIONS AND INDICATIONS

Inhaled steroids are used to decrease the inflammatory response in the airway.

In an airway swollen and narrowed by inflammation and swelling, this action will increase airflow and facilitate respiration.

Inhaling the steroid tends to decrease the numerous systemic effects that are associated with steroid use.

INHALED STEROIDS

THERAPEUTIC ACTIONS AND INDICATIONS

When administered into the lungs by inhalation, steroids decrease the effectiveness of the inflammatory cells.

This has two effects:

decreased swelling associated with inflammation

and promotion of beta adrenergic receptor activity= which may promote smooth muscle relaxation and inhibit broncho-constriction.

INHALED STEROIDS

CONTRAINDICATIONS/CAUTIONS

Inhaled corticosteroids are not for emergency use and not for use during an acute asthma attack or status asthmaticus.

They should not be used during pregnancy or lactation.

INHALED STEROIDS

ADVERSE EFFECTS

Adverse effects are limited because of the route of administration

Respiratory= Sore throat, hoarseness, coughing, dry mouth, and pharyngeal and laryngeal fungal infections are the most common side effects encountered.

If a patient does not administer the drug appropriately or develops lesions that allow absorption of the drug, the systemic side effects associated with steroids may occur.

INHALED STEROIDS

Implementation

Do not administer the drug to treat an acute asthma attack or status asthmaticus, as these drugs are not intended for treatment of acute attack.

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Taper systemic steroids carefully during the transfer to inhaled steroids; deaths have occurred from renal insufficiency with sudden withdrawal.

Have the patient use decongestant drops before using the inhaled steroid to facilitate penetration of the drug if nasal congestion is a problem.

INHALED STEROIDS

Implementation

Have the patient rinse the mouth after using the inhaler, as this will help to decrease systemic absorption and decrease GI upset and nausea

Monitor the patient for any sign of respiratory infection; continued use of steroids during an acute infection can lead to serious complications related to the depression of the inflammatory and immune responses.

INHALED STEROIDS

Evaluation

Monitor patient response to the drug (improved breathing).

Monitor for adverse effects (nasal irritation, fever, GI upset)

Cromolyn

Administered by INHALATION is a drug that is frequently used in the treatment of asthma.

It does not have bronchodilating or anticholinergic effects and does not fit into any other pharmacological class.

Cromolyn

THERAPEUTIC ACTIONS AND INDICATIONS

Cromolyn is a mast cell stabilizer.

It works at the cellular level to inhibit the release of histamine (released from mast cells in response to inflammation or irritation).

It is inhaled from a capsule and may not reach its peak effect for 1 week.

It is recommended for the treatment of chronic bronchial asthma, exercise-induced asthma, and allergic rhinitis.

Cromolyn

CONTRAINDICATION / CAUTIONS

Cromolyn cannot be used during an acute attack, and patients need to be instructed in this precaution.

Allergy to seafoods

It is not recommended for pregnant or nursing women or children under the age of 6 years.

Cromolyn

ADVERSE EFFECTS

Few adverse effects have been reported with the use of cromolyn

swollen eyes, headache, dry mucosa, and nausea.

Cromolyn

Implementation

Review administration procedures with the patient periodically; proper use of the delivery device is important in maintaining the effectiveness of this drug.

Caution the patient not to discontinue use abruptly; cromolyn should be tapered slowly if discontinuation is necessary to prevent rebound adverse effects.

Caution the patient to continue taking this drug, even in symptom-free periods, to ensure therapeutic levels of the drug.

Cromolyn

Implementation

Administer oral drug one-half hour before meals and at bedtime, which will promote continual drug levels and relief of asthma.

Advise the patient not to wear soft contact lenses; if cromolyn eye drops are used, lenses can be stained.

Provide thorough patient teaching, including the drug name and prescribed dosage, measures to help avoid adverse effects, warning signs that may indicate problems, and the need for periodic

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monitoring and evaluation to enhance patient knowledge about drug therapy and to promote compliance.

Cromolyn

Evaluation

Monitor patient response to the drug (improved breathing).

Monitor for adverse effects (drowsiness, headache, GI upset, local irritation).

Evaluate the effectiveness of the teaching plan (patient can name drug, dosage, adverse effects to watch for, specific measures to avoid adverse effects.

Anti-infective drugs

Selecting an anti-infective drug

First, the microorganism must be isolated and identified generally through growing a culture

Then its susceptibility to various drugs must be determined

Location of the infection must be considered

Cost of drugs as well as its potential adverse effects and allergies

Antibacterial drugs

Also known as antibiotics

Drugs that either kill or inhibit the growth of bacteria

Mainly used to treat systemic bacterial infections

Antibacterial drugs include:

1. aminoglycosides

2. cephalosporins

3. tetracyclines

4. lincomycin derivatives

5. macrolides

6. vancomycin

7. carbapenems

8. monobactams

9. fluoroquinolones

10. sulfonamides

11. nitrofurantoin

Aminoglycosides

Are bactericidal (destroy bacteria)

Effective against:

- gram-negative bacilli

- some aerobic gram-positive bacteria

- mycobacteria

- some protozoa

Currently in use includes:

- amikacin sulfate

- gentamicin sulfate

- kanamycin sulfate

- neomycin sulfate

- streptomycin sulfate

- tobramycin

Pharmacokinetics:

- absorbed poorly form the GIT

- usually given parenterally

- IV/IM absorption is rapid and complete

- distributed widely in extracellular fluid

- readily crossess the placental barrier but not BBB

- arent metabolized

- excreted primarily in the kidneys

Pharmacodynamics:

- by binding to the bacteria’s 30S subunit, specific ribosomes thereby interrupting CHON synthesis and causing the bacteria to die

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Pharmacotherapeutics:

- infections caused by gram-negative bacilli

- serious nosocomial, gram-negative bacteremia, peritonitis, pneumonia

- UTI’s

- infections of the CNS

Penicillins

Remain the most important and useful antibacterial drugs

Divided into four groups:

- natural penicillins ( penicillin G benzathine, penicillin G potassium, penicillin G procaine, penicillin G sodium, penicillin V potassium)

- penicillinase-resistant penicillines (dicloxacillin sodium, nafcillin sodium, oxacillin sodium)

- aminopenicillins (amoxicillin, ampicillin)

- extended-spectrum penicillins (carbenicillin indanyl sodium, ticarcillin disodium)

Pharmacokinetics:

- absorption of oral penicillin varies and depends on such factors as:

1. particular penicillin used

2. pH of the stomach and intestine

3. presence of food in the GIT

- most penicillins are given on an empty stomach (1 before or 2 hours after meal)

- penicillins that can be given wihtout regard to meals: amoxicillin, penicillin V and amoxicillin-clavulanate K

- most penicillins are excreted 60% unchanged by the kidneys (nafcillin and oxacillin – bile)

Pharmacodynamics:

- they bind reversibly to several enzymes (penicillin-binding proteins) outside the bacterial cytoplasmic membrane

Pharmacotherapeutics:

- wide spectrum

- they cover gram-positive, gram-negative, and anaerobic organisms

Cephalosporins

Are grouped into generations according to their effectiveness against different oraganisms, characteristics and development

First generation

Cefadroxil

Cefasolin

Cephalexin

cephadrine

Second generation

Cefaclor

Cefotetan

Cefprozil

Ceftibuten

cefuroxime

Third generation

Cefdinir

Cefoperazone

Cefotaxime

Ceftazidime

ceftriaxone

Fourth generation

Cefditoren

cefepime

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Are administered parenterally (they are’nt absorbed from the GIT)

Some are absorbed from the GIT but food usually decreases their absorption rate

Cefuroxime and cefpodoxime – increased absorption when given with food

Pharmacotherapeutics

- 1st generation – gram positive organisms

- used to treat staph and strep infections

- 2nd generation – gram – negative

- 3rd generation – drug of choice for enterobacter,P.

aeruginosa

- 4th generation – gram positive and

negative

Tetracyclines

Broad-spectrum antibacterial

Classified as:

- intermediate acting (demeclocycline Hcl)

- long acting (doxycycline and minocycline)

Pharmacokinetics:

- absorbed from the duodenum when taken orally

- distributed widely into body tissues and fluids concentrated in bile

- excreted primarily by kidneys

- doxycycline – feces

- minocycline – enterohepatic recirculation

Pharmacodynamics:

- they penetrate the bacterial cell by an energy-dependent process

- within the cell, they bind primarily to a subunit of the ribosome, inhibiting the CHON synthesis required for maintaining the bacterial cell

Pharmacotherapeutics:

- gram-positive/negative aerobic and anaerobic bacteria

- spirochettes

- mycoplasma

- rickettsiae

- chlamydia

- some protozoa

- tetracyclines are used to treat:

1. rocky mountain spotted fever

2. Q fever

3. lyme dse.

Macrolides

Includes erythromycin and derivatives such as:

- estolate

- ethylsuccinate

- gluceptate

- lactobionate

- stearate

Other macrolides includes:

- azithromycin

- clarithromycin

Pharmacokinetics:

- acid-sensitive (it must be buffered or have an enteric coating to prevent destruction by gastric acid)

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- erythromycin – absorbed in the duodenum

- metabolized in the liver

- excreted in bile in high concentrations, small amounts are excreted in urine

Pharmacodynamics:

- inhibit RNA-dependent CHON synthesis by acting on a small portion of the ribosome

Pharmacotherapeutics:

- drug of choice for treating Mycoplasma pneumoniae infections as well as pneumoniae caused by Legionella pneumophila

Carbapenems

Are a class of beta-lactam antibacterials that includes:

- imipenem-cilastatin Na

- meropenem

- ertapenem

Quinolones

Structurally similar synthetic antibacterial drugs

Primarily administered to treat UTI’s, URTI, pneumonia, gonorrhea

Includes:

- ciprofloxacin

- gatifloxacin

- levofloxacin

- moxifloxacin

- norfloxacin

- ofloxacin

Sulfonamides

First effective systemic antibacterial drugs

Includes:

Co-trimoxazole (sulfamethoxazole and trimethoprim)

Sulfadiazine

sulfisoxazole

Sulfonamides

treat UTI

sulfamethazole(Gantanol)

Sulfixazole(Gantrisin)

sulfazaline( Azulfidine)

sulfamethazole and trimethoprim(Bactrim and Septra)

Sulfonamides

S/E;

nausea and vomiting (gastric irritation) decreased absorption of folacin

rash

malaise

blood dyscrasias

crystaluria(drug precipitation in acidic urine)

stomatitis , hypersensitivity and photosensitivity

Sulfonamides

I

increase OFI

maintain alkaline urine

monitor blood work – megaloblastic anemia(dec. folacin)

potentiates anticoagulant and oral hypoglycemic effects

Antiviral drugs

Used to prevent or treat viral infections ranging from influenza to HIV

Major antiviral drug classes used to treat systemic infections include:

Synthetic nucleosides

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Nucleoside analog reverse transcriptase inhibitors (NRTIs)

Non-nucleoside reverse transcriptase inhibitors(NNRTIs)

Nucleotide analog reverse transcriptase inhibitors

Protease inhibitors

ANTIVIRALS

PROVIDE PROPHYLAXIS WHEN EXPOSURE TO VIRAL INFECTION HAS OCCURRED

Acyclovir sodium (Zovirax)

Amantadine Hcl (Symmetrel)

Interferon(Roferon – A)

AZT

Idoxuridine ( Stoxil)

ANTIVIRALS

cns stimulation and orthostatic hypotension, nephrotoxicity, dizziness and constipation

Nsg. Consideration:

support natural defense

encourage high fiber foods

evaluate response

Synthetic nucleosides

Group of drugs used to treat various viral syndromes that can occur in immunocompromised patients including HSV and CMV

Drugs in this class includes:

Acyclovir

Famciclovir

Ganciclovir

Valacyclovir Hcl

Valgancyclovir Hcl

ANTIVIRALS

PROVIDE PROPHYLAXIS WHEN EXPOSURE TO VIRAL INFECTION HAS OCCURRED

Acyclovir sodium (Zovirax)

Amantadine Hcl (Symmetrel)

Interferon(Roferon – A)

AZT

Idoxuridine ( Stoxil)

ANTIVIRALS

cns stimulation and orthostatic hypotension, nephrotoxicity, dizziness and constipation

Nsg. Consideration:

support natural defense

encourage high fiber foods

evaluate response

Anti Tuberculars

administered in combination over a prolonged time period to decrease the possibility of mycobacterial drug resistance

first line :

ethambutol-mycobacterial RNA

Isoniazid – mycobacterial cell wall

Paraaminosalicylic acid preparation(PAS)-mycobacterial folic acid synthesis

Rifampin-interferes with mycobacterial RNA

Streptomycin sulfate – inhibits mycobacterial protein synthesis

second line:

pyrazinamide

ethionamide

capriomycin

Anti Tuberculars

S/E:

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GI irritation

suppressed absorption of fat and B complex , -spec. folacin and B12, depletion of B6 by isoniazid

dizziness,CNS and liver disturbances

blod dyscrasias

streptomycin : ototoxicity( direct auditory{eight cranial nerve}toxicity)

ethambutol: visual disturbances ( direct optic nerve toxicity)

Anti Tuberculars

nursing care:

support defense mechanisms

obtain sputum specimens for acid fast bacillus

monitor blood work

enforce compliance , avoid alcohol

instruct regarding nutriitonal deficits

Rifampin – urine dark orange

Streptomycin: auditory exams

Ethambutol – visual exams

PZA – liver functions

Anti fungals

used to treat sytemic and localized fungal infections

Amphotericin ( Fungizone)

Fluconazole (Diflucan )

Griseofulvin ( Grisactin )

Nystatin ( Mycostatin, Nilstat )

Anti - fungals

nausea and vomiting( gastric irritation)

headache( neurotoxicity)

fever and chills ( blood dyscrasias )

paresthesia( neurotoxicity)

review proper method of application

assess vital signs, throughout course of therapy

evaluate clients response

Anti fungals

Amphotericin B

use infusion control device and protect from light

monitor blood works-hypokalemia and hypomagnesemia

Griseofulvin – assess for antagonism if patients are taking anti coagulants. avoid sunlight

topical prep- wash drug stained clothing with soap and water., report signs of local irritation

Anti parasitics

interfere with parasite metabolism and reproduction, helminthic as well as protozoal infestations respond to this class of drugs

Antihelmithic

Mebendazole ( Vermox)

Piperazine ( Vermazine )

Pyrivinium Pamoate ( Povan)

Amebicides

Chloroquine HCl ( Aralen)

Emetine Hcl

Metronidazole ( Flagyl)

Antimalarials

Chloroquine HCl ( Aralen)

Hydroxychloroquine SO4 ( Plaquenil)

Pyrimethamine ( Darapime)

Primaquine PO4

Anti parasitics

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antihelminthics-GI irritation, CNS disturbance, skin rash

amebicides – GI iiritation, blood dyscrasias, skin rash, headache, dizziness

Antimalarials-nausea and vomiting, blood dyscrasias, visual disturbances

Anti parasitics

administer drug with meals and assess VS

monitor blood works and instruct client about proper hygiene

use safety precautions if CNS effects are manifested

antimalarials – frequent visual examinations

evaluate response to treatment and understanding of therapy

Pharmacology of the anti-inflammatory agents

ANTI-INFLAMMATORY AGENTS

The anti-inflammatory response is designed to protect the body from injury and pathogens.

It employs a variety of potent chemical mediators to produce the reaction that helps to destroy pathogens and promote healing

Inflammatory Physiology

Inflammation: ETIOLOGY

Physical Agents

Mechanical objects causing trauma to objects

excessive heat & cold (burn & frostbite)

radiation

Chemical Agents

external irritants – strong acids, alkalis, irritating gasses

internal irritants – substances manufactured within the body such as excessive HCL in the stomach

Microorganisms – group of bacteria, viruses, fungi, protozoa, Rickettsia

Inflammation

Characteristic Signs:

Pain (Dolor)

Swelling /Edema (Tumor)

Redness (Rubor)

Heat (calor)

Impaired function of the part (severe injury) Functio laesa

Fig. 4.9

ANTI-INFLAMMATORY AGENTS

There are many different types of drugs utilized as anti-inflammatory agents.

Steroids like cortisone, beclomethasone, etc, systemically block inflammatory and immune responses.

Anti-histamines block the release of Histamine.

Another major class of drugs is termed Non-Steroidal Anti-inflammatory drug.

Drugs

The Salicylates

These agents are some of the oldest anti-inflammatory and pain reliever agents.

Acetylsalicylic acid (aspirin)

Choline magnesium trisalicylate

Choline salicylate

Mesalamine

Osalazine

Salsalate

Sodium thiosalicylate

Diflusinal (a derivative of salicylic acid)

Salicylates

Classification: Non-Steroidal Anti-inflammatory agents

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Dynamics: Inhibit the enzyme that produces prostaglandins

Kinetics: Administered orally and parenterally

Common side-effects Peptic ulceration, bleeding

NR: Administer with foods; bleeding precaution

Salicylates

Given for pain, fever and inflammation

Effectiveness is determined if manifestations of pain, fever and inflammation resolve.

The Salicylates

Mechanism of Action of the Salicylates

Salicylates inhibit the synthesis of prostaglandin, an important mediator of the inflammatory reaction.

The Salicylates

Mechanism of Action of the Salicylates

The fever lowering property (antipyretic effect) of salicylates is related to the blocking of a prostaglandin mediator of pyrogens

Aspirin affects platelet aggregation by inhibiting the synthesis of thromboxane A, a potent vasoconstrictor normally increases platelet aggregation

The Salicylates

Therapeutic Use of the Salicylates

Mild to moderate pain

Fever

Inflammatory conditions

Prevention of ischemic stroke

Aspirin is also given to patients with CAD, angina or previous history of MI to reduce the risk of myocardial infarction and death

The Salicylates

Pharmacokinetic profile of the Salicylates

Aspirin is well absorbed from the GIT.

Because of the GI effects, the Salicylates should be taken with meals

The Salicylates

The Adverse Effects of Salicylate Use

GIT- gastric ulceration , nausea, dyspepsia, heartburn and epigastric discomfort.

VASCULAR- bleeding abnormalities can be expected. Patients can have occult blood loss and spontaneous small hemorrhages.

The Salicylates

The Adverse Effects of Salicylate Use

SALICYLISM- this condition can occur with higher levels of aspirin. Acute salicylate toxicity may occur at 20 to 25 grams dosage intake in an adult, or about 4 grams in children

The Salicylates

Acute MILD Salicylism early sings/symptoms- Manifestations are ringing in the ear, dizziness, mild bronchospasm, nausea, vomiting, mental confusion and lassitude.

Acute SEVERE Salicylism late signs/symptoms- Metabolic ACIDOSIS, tachypnea, respiratory ALKALOSIS, hemorrhage, pulmonary edema, pyrexia, coma convulsions, and shock, hypo tension and multiple organ collapse (renal, cardiovascular and respiratory)

The Salicylates

Contraindications and Cautions with Salicylate Use

The use of Salicylates is contraindicated in the presence of known allergy to Salicylates, NSAIDs, and tartrazine. Impaired kidney function, pregnant and lactating women should avoid aspirin

A condition known as Reye’s syndrome can possibly occur if children and adolescents are given aspirin during a viral illness like chicken pox and influenza.

The Salicylates

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Nursing interventions for the Salicylates

Administer Salicylates WITH FOOD if GI upset is likely. Provide small, frequent meals to alleviate GI effects

Administer drug as indicated and monitor therapy to prevent toxicity

Monitor for severe drug effects= Tinnitus!!

Provide supportive care and comfort measures to support the effects of Salicylates in relieving pain and inflammation

The Salicylates

Nursing interventions for the Salicylates

For aspirin toxicity, the doctor orders sodium bicarbonate to ALKALINIZE the urine for faster drug excretion

The NSAIDS

Popularly called the NSAIDs, these agents are the most commonly used drugs for inflammation and pain.

The groups of NSAIDs are:

Salicylates

Propionic Acids and derivatives

Fenoprofen

Flurbiprofen

Ibuprofen

Ketoprofen

Naproxen

Oxaprozin

The NSAIDS

The groups of NSAIDs are:

Acetic Acids

Diclofenac (phenylacetic)

Etodolac (phenylacetic)

Ketorolac (phenylacetic)

Para-Chlorobenzoic Acid (indoles)

Indomethacin (chlorobenzoic acid)

Nabumetone (chlorobenzoic acid)

Sulindac (chlorobenzoic acid)

Tolmetin (chlorobenzoic acid)

Fenamates- Anthranilic acids

Mefenamic acid

Meclofenamate

Diflusinal

Piroxicam

The NSAIDS

Mechanism of Action of the NSAIDs

The anti-inflammatory, analgesic, and antipyretic effects are largely related to inhibition of prostaglandin synthesis.

The NSAIDS

Mechanism of Action of the NSAIDs

The NSAIDs block two enzymes known as cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) to stop turning arachidonic acid into prostaglandin.

The NSAIDS

Mechanism of Action of the NSAIDs

By interfering with this part of the inflammatory reaction, NSAIDs block inflammation before all of the signs and symptoms can develop

The NSAIDS

Therapeutic Use of NSAIDs

Moderate to severe pain

Inflammatory conditions like rheumatoid arthritis, osteoarthritis

Primary dysmenorrhea

Sometimes, for fever reduction

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The NSAIDS

Contraindication and Cautions with the use of NSAIDs

Allergy to any NSAID or salicylate; with cardiovascular dysfunction or hypertension due to the varying effects of prostaglandins;

With peptic ulcer or known GI bleeding because of the potential exacerbation; and during pregnancy and lactation because of potential effects on the baby

The NSAIDS

The Adverse Effects of NSAIDs

GIT- patients experience peptic Ulceration, dyspepsia, GI pain, constipation or diarrhea, and flatulence. The potential for GI bleeding should alert the nurse.

CNS- Patients may complain of dizziness, somnolence and fatigue.

VASCULAR- bleeding and bone marrow depression have been reported in chronic users.

The NSAIDS

The Selective COX-2 inhibitors- Second generation NSAIDs

Because older NSAIDs inhibit both the COX-1 and COX-2, they produce more side effects.

By inhibiting COX-1, protection of stomach lining is decreased and the clotting time is also decreased.

The selective COX-2 inhibitors only inhibit COX-2 present in inflammatory cells; thereby the GI effects are minimal.

The NSAIDS

The Selective COX-2 inhibitors- Second generation NSAIDs

Examples are: The “COXIB”s

CELECOXIB (Celebrex)

ROFECOXIB

NIMESULIDE

The NSAIDS

IMPLEMENTATION

Assure proper drug administration

Administer with food if GI upset will occur

Provide supportive and comfort measures to deal with adverse effects: small frequent meals, safety measures if dizziness occurs, etc.

Provide patient teaching regarding drug, dosage, side effects, precaution and warnings

The NSAIDS

IMPLEMENTATION

Remind the patient that piroxicam can take up to 2 weeks before therapeutic effect can be seen

The NSAIDS

EVALUATION

Evaluate drug effects such as decreasing pain and subsiding inflammatory response

Monitor for adverse effects

Monitor for drug-drug interaction

NSAIDS

N= o alcohol, aspirin

S= ide effects: “BIRTH”

B-one marrow depression, BLEEDING,

I-ncreased GI distress, R- renal toxicity, T- tinnitus and H- hepatotoxicity

A= aspirin sensitivity= Don’t give NSAIDS

I= Inhibits prostaglandin

D= Do TAKE with food

S= top 5-6 days before surgery

Paracetamol

Acetaminophen is widely used to treat moderate pain and fever when aspirin and NSAIDs cannot be utilized

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Paracetamol

Acetaminophen lacks an anti-inflammatory property that makes it ineffective for inflammation.

Paracetamol

Mechanism of Action of Acetaminophen

Acetaminophen acts directly on the thermoregulatory cells in the hypothalamus to cause sweating and vasodilation; this in turn causes the release of heat and lowers fever.

Analgesic action is still unclear

Paracetamol

Therapeutic use of Acetaminophen

Moderate pain

Fever

Prophylaxis of children receiving DPT immunization

Paracetamol

Contraindications and Precaution with the use of Acetaminophen

Acetaminophen is contraindicated in the presence of allergy to the drug.

Hepatic dysfunction and chronic alcoholism are important consideration.

Paracetamol

Adverse Effects of Acetaminophen

CNS- headache

Liver- hepatotoxicity is a potential adverse effect that is usually fatal. This happens in drug overdose. N-acetylcysteine is the antidote

Hemolytic anemia, renal dysfunction, skin rash

NARCOTIC AGONISTS

These are called agonists because they react with the opiod receptors throughout the body to cause analgesia, sedation and euphoria.

NARCOTIC AGONISTS

The following are examples of narcotic agonists

Morphine

Codeine

Meperidine

Methadone

Fentanyl

NARCOTIC AGONISTS

Therapeutic Use of Narcotic Agonists

Sedation

Analgesia

Antitussives

Adjunct to general anesthesia

Pain, acute and chronic pain

Pre-operative medication

NARCOTIC AGONISTS

Contraindications and Cautions: Use of Narcotics

The narcotic agonists are contraindicated in the following conditions: allergy to narcotics, pregnancy, labor and lactation because of potential effects on the fetus/neonate including respiratory depression, diarrhea caused by poisons and following biliary surgery.

NARCOTIC AGONISTS

Adverse Effects of the Narcotic Agonist

CNS- respiratory depression, sedation, lightheadedness, hallucinations, dizziness, anxiety, psychoses, pupil CONSTRICTION

GIT- Nausea, vomiting (due to the stimulation of the chemoreceptor trigger zone), constipation (due to decreased GIT motility) and biliary spasm (esp. morphine)

GU – ureteral spasms, urinary retention, hesitancy, and loss of libido. These may be due to the direct receptor stimulation or to CNS activation of sympathetic pathways.

Triad of OPIOID toxicity

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Respiratory depression

Coma

PIN POINT pupils

NARCOTIC AGONISTS

IMPLEMENTATION

Provide a narcotic antagonist and equipment for ventilation on standby to support the patient in case of severe reaction

Monitor timing of analgesic doses because prompt administration may provide a more acceptable level of analgesia leading to quicker relief of pain.

Utilize additional measures to relieve pain such as back rub, massage, stress reduction, hot/cold packs to increase the effectiveness of narcotic use and reduce pain.

NARCOTIC AGONISTS

IMPLEMENTATION

Assure patients that intake of medical doses of narcotics will NOT lead to addiction

Advise to eat a high-fiber diet with liberal intake of fluids to combat constipation

NARCOTIC AGONISTS

IMPLEMENTATION

Assure patients that intake of medical doses of narcotics. Warn patients about orthostatic hypotension and sedation so as to modify their activities like driving , performing delicate tasks and operating machineries

Take the drug with food may alleviate loss of appetite and nausea.

Advise patient to avoid use of alcohol, anti-histamine and other over-the counter drugs while taking narcotics.

NARCOTIC AGONISTS

EVALUATION

Monitor the response of the patient to the drug such as relief of pain, sedation and cough suppression

The NARCOTIC AGONIST-ANTAGONIST

These drugs stimulate certain opiod receptors but BLOCK other receptors

They have less abuse potential than pure narcotic agonists but their analgesic properties may be equal.

The NARCOTIC AGONIST-ANTAGONIST

The following are the narcotic agonists-antagonist:

Buphenorphine

Butorphanol

Dezocine

Nalbuphine (Nubain)

Pentozacine

The NARCOTIC AGONIST-ANTAGONIST

Mechanism of Action of Narcotic Agonist-Antagonist

The mixed narcotics act at specific opiod receptor sites in the CNS to produce analgesia, sedation, euphoria and hallucinations.

They also block opiod receptor that may be stimulated by the pure agonists.

The NARCOTIC AGONIST-ANTAGONIST

Therapeutic Use of Mixed Narcotics

Relief of moderate to severe pain

Addition to general anesthesia

Relief of pain labor and delivery

The NARCOTIC AGONIST-ANTAGONIST

Adverse Effects of the Mixed Narcotics

Respiratory depression with apnea and suppression of the cough reflex

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Nausea and vomiting are due to the stimulation of the CTZ

Constipation due to impaired GIT motility and Biliary spasms due to stimulation of bile duct contraction

CNS opiod receptor stimulation will cause: hallucination, sedation, euphoria lightheadedness, dizziness, psychoses, anxiety, and impaired mental processes

GU effects are urinary hesitancy, retention, loss of libido and ureteral spasms.

The NARCOTIC AGONIST-ANTAGONIST

IMPLEMENTATION

Provide a narcotic antagonist and equipment for resuscitation in cases of very severe reactions to provide supportive care

Institute comfort measures and safety precautions such as side rails, assistance in ambulation, bowel program and small frequent meals

The NARCOTIC AGONIST-ANTAGONIST

IMPLEMENTATION

Provide additional pain relieving measures such as hot/cold packs, stress reduction, massage and back rubs

Assure patients that addiction is very minimal

Provide client teaching including drug name, prescribed dosage, measures to handle adverse effects, warning sings and the need for regular evaluation

The NARCOTIC ANTAGONISTS

These are drugs that bind strongly to opiod receptors but DO NOT activate them.

The following are the narcotic antagonists:

Nalmefene

Naloxone

Naltrexone

The NARCOTIC ANTAGONISTS

The Mechanism of Action of Narcotic Antagonist

The narcotic antagonists block opioid receptors and reverse the effects of opoids, including respiratory depression, sedation, and psychomimetic effects.

The NARCOTIC ANTAGONISTS

Therapeutic Use of narcotic antagonists

Reversal of the effects of narcotics and over dosage- naloxone and nalmefene are used to manage these conditions.

Naloxone is used to diagnose narcotic overdose using the naloxone challenge test

Narcotic dependence and alcoholic dependence- naltrexone is used in the management of these conditions.

The NARCOTIC ANTAGONISTS

The Adverse Effects of Narcotic Antagonists

The most common is acute narcotic abstinence syndrome that is characterized by nausea, vomiting, sweating, tachycardia, hypertension, tremulousness, and anxiety.

CNS- excitement and reversal of analgesia

CV effects- tachycardia, blood pressure changes, arrhythmias and pulmonary edema.

The NARCOTIC ANTAGONISTS

IMPLEMENTATION

Maintain open airway and provide artificial ventilation and cardiac massage as needed in severe reaction

Administer naloxone challenge before giving naltrexone because of serious risk of acute withdrawal

Monitor patient continually adjusting the dosage as needed during treatment of acute overdose

The NARCOTIC ANTAGONISTS

IMPLEMENTATION

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Ensure that patient is receiving naltrexone as part of a comprehensive or alcohol withdrawal program

Institute comfort measures such as side rails, assistance with ambulation, bowel program, environmental stimulation control and small frequent feedings to relieve GI irritation.

ANTIGOUT

Gout is a metabolic disease characterized by inflammation of the joints and deposition of uric acid crystals in other parts of the body.

The joint most commonly affected is the metatarsal joint of the big toe.

The etiologies of gout may be increased accumulation of uric acid or ineffective clearance of uric acid in the kidney.

Drugs for Gout

ANTIGOUT: Colchicine

ANTI-INFLAMMATORY Gout Drug

Cochicine is an anti-inflammatory drug that inhibits the migration of leukocytes to the inflamed site. Its action is attribute to the inhibition of WBC microtubule assembly.

Indomethacin is also another drug used because it can reduce WBC migration and phagocytosisà decreased inflammation

ANTIGOUT: Colchicine

ANTI-INFLAMMATORY Gout Drug

It is effective in alleviating acute symptoms of gout but not in other conditions. It does not inhibit uric acid synthesis and does not promote uric acid excretion.

It is not recommended for clients with severe renal, cardiac or GI problems.

Gastric irritation is a common problem and it should be taken with food. Other side effects are Nausea, vomiting, diarrhea, abdominal pain.

ANTIGOUT

URIC ACID INHIBITOR: ALLOPURINOL

Allopurinol is the drug given to patients to reduce the uric acid synthesis.

It is used frequently as prophylaxis to prevent gouty attacks.

ANTIGOUT

URIC ACID INHIBITOR: ALLOPURINOL

Allopurinol

Increased fluid intake is recommended to promote diuresis and prevent alkalinization of the urine.

Nurses must encourage at least 3 liters of fluid per day.

ANTIGOUT

Pharmacodynamics: Action of Allopurinol

This drug inhibits the production of uric acid by inhibiting the enzyme xanthine oxidase. This also improves the solubility of the uric acid crystals.

Onset of action is 1 hour, and peak is 2-4 hours. The effect of the drug may not be apparent for few days to a few weeks.

Nurses must teach this to the patient to avoid non-compliance.

ANTIGOUT

Pharmacokinetics

It is given orally in the management of gout. Majority of the drug is absorbed from the GIT. The half-life is 2-3 hours.

Most of the drugs and metabolites are excreted in the feces and some in the urine. Its onset of action is 1 hour and peak is 2-4 hours.

ANTIGOUT

Adverse Effects

GIT- anorexia, nausea, vomiting, diarrhea and stomatitis.

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CNS- dizziness, peripheral neuritis and vasculitis

Acute gouty attacks if allopurinol is given during the acute stage of the disease.

Reportable manifestations are rashes and swelling.

ANTIGOUT: Allopurinol

Patient should be warned not to drink alcoholic beverages and to avoid foods that are rich in uric acid- aged foods, legumes, beer, internal organ meats.

Increase fluid intake to 3 liters per day

Report occurrence of rashes

Take with meals

Allopurinol and Gout

G= ulp 10-12 glasses of fluid/day. GI distress is undesirable

O=utput and input should be monitored closely

U=ric acid production decreases and USE NO ALCOHOL

T=ake AFTER meals when stomach is full

ANTIGOUT

URICOSURIC DRUGS: Probenecid

These agents are weak acids and can cause increased excretion of uric acids in the kidney by competing with uric acid, thus inhibiting its re-absorption

They are effective in alleviating chronic gout but they are not used in acute attacks.

ANTIGOUT

URICOSURIC DRUGS

Probenecid- is a uricosuric agent that blocks the re-absorption of uric acid and promotes its excretion.

It causes gastric irritation and should be taken with meals.

ANTIGOUT

URICOSURIC DRUGS

Sulfinpyrazone- a metabolite of phenylbutazone is more potent than probenecid.

It should also be taken with meals because of gastric irritation.

Severe blood dyscrasias can occur.

GOLD compounds

Chrysotherapy (heavy metal therapy) is the treatment of these rheumatic conditions with the use of gold compounds.

GOLD compounds

There are currently 3 gold compounds for use:

Auranofin- is an oral agent used for long-term therapy

Aurothioglucose- parenteral gold IM preparation given in early disease

Gold Sodium Thiomalate- also a parenteral IM preparation of gold salts

GOLD compounds

The Mechanism of action of Gold Salts

Gold salts are ingested by macrophages and inflammatory cells resulting in the inhibition of phagocytosis.

It depresses the migration of leucocytes and suppress prostaglandin activity

GOLD compounds

It is important for the nurse to remember that the therapeutic effect of these agents can take up to 8 weeks or 2 months (if given parenterally) or 3-6 months (if given orally)

GOLD compounds

The Adverse Effects of Gold Compounds

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Tissue/local effects- these are associated with the deposition of the gold metal in the tissues. Stomatitis, dermatitis, glossitis, pharyngitis, laryngitis, colitis, diarrhea and GIT inflammation.

Other effects- Hypersensitivity, BONE MARROW DEPRESSION , RENAL INSUFFICIENCY and anaphylaxis

Nurses must instruct the patient to report metallic taste in the mouth as it signals toxicity.

GOLD compounds

Nursing Responsibilities

Monitor CBC, urinalysis and liver enzymes

Teach the client to avoid strong lights to prevent dermatitis

Proper oral care to manage stomatitis

Explain to patients that therapeutic effect can be expected after several months of intake and administration

STEROIDS

Replaces the steroids in the body

Cortisol, cortisone, betamethasone, and hydrocortisone

STEROIDS

These drugs enter the cells and bind to receptors

They inhibit the enzyme phospholipase

STEROIDS

Corticosteroids are used topically and locally to achieve the desired anti-inflammatory effects at a particular site

Examples:

Prednisone

Bethamethasone

Prednisolone

Fludrocortisone

STEROIDS

Side-effects

HYPERglycemia

Increased susceptibility to infection (immunosuppression)

Hypokalemia

Edema

Peptic ulceration

STEROIDS

Side-effects

If high doses- osteoporosis, growth retardation, peptic ulcer, hypertension, cataract, mood changes, hirsutism, and fragile skin

STEROIDS

Nursing responsibilities

1. Monitor VS, electrolytes, glucose

2. Monitor weight edema and I/O

STEROIDS

Nursing responsibilities

3. Protect patient from infection

4. Handle patient gently

5. Instruct to take meds WITH MEALS to prevent gastric ulcer formation

STEROIDS

Nursing responsibilities

6. Caution the patient NOT to abruptly stop the drug

7. Drug is tapered to allow the adrenal gland to secrete endogenous hormones

STEROIDS

Evaluation:

The drugs are effective if there is:

1. Relief of signs and symptoms of inflammation

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2. Return of adrenal function to normal

Pharmacology of the GIT system

LECTURE Outline

REVIEW the Anatomy of the GIT

REVIEW the Physiology of the GIT

Review common GI drugs in the following categories:

1. Drugs affecting GI secretions

2. Laxatives

3. Anti-diarrheals

4. Emetics and anti-emetics

Drugs affecting GI secretions

There are five types of drugs that affect gastric acid secretions and are useful for the treatment of peptic ulcer.

1. Histamine (H2) receptor antagonist/blockers

2. Antacids

3. Proton pump inhibitors

4. Mucosal protectants

5. Prostaglandin analogs

Drugs affecting secretions: anti ulcer

General indication of the drugs affecting gastric acid secretion

Peptic ulcer

Gastritis

Patient on NPO to prevent stress ulcer

General time of administration of the drugs affecting gastric acid secretion

Pharmacodynamics

Histamine (H2) receptor blockers

These drugs BLOCK the release of hydrochloric acid in the stomach in response to gastrin

Drugs affecting GI secretions

Antacids

These drugs interact with the gastric acids at the chemical level to neutralize them

Drugs affecting GI secretions

Proton pump inhibitors

These drugs suppress the secretion of hydrochloric acid into the lumen of the stomach

Drugs affecting GI secretions

Mucosal protectants

These are agents that coat any injured area in the stomach to prevent further injury from acid

Drugs affecting GI secretions

Prostaglandin analogs

These are agents that inhibit the secretion of gastrin and

increase the secretion of mucus lining of the stomach, providing a buffer.

The H2 Blockers- “tidines”

Prototype: Cimetidine

1. Ranitidine

2. Famotidine

3. Nizatidine

The H2 Blockers- “tidines”

Pharmacodynamics: Drug Action

The H2 blockers are antagonists at the receptors in the parietal cells of the stomach.

The blockage results to inhibition of the hormone gastrin.

There will be decreased production of gastric acid from the parietal cells.

Also, the chief cells will secrete less pepsinogen.

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The H2 Blockers- “tidines”

Therapeutic use of the H2 blockers

Short-term treatment of active duodenal ulcer or benign gastric ulcer

Treatment of hypersecretory conditions like the Zollinger-Ellison syndrome

Prevention of stress-induced ulcers and acute GI bleeding

Treatment of erosive GERD (reflux disease)

Relief of Symptoms of heart burn and acid indigestion

The H2 Blockers- “tidines”

Precautions and Contraindications

Any known allergy is a clear contraindication to the use of the agents.

Conditions such as pregnancy, lactation, renal dysfunction and hepatic dysfunction should warrant cautious use.

Nizatidine can be used in hepatic dysfunction.

The H2 Blockers- “tidines”

Dynamics- Side effects/adverse effects

GIT= diarrhea or constipation

CNS= Dizziness, headache, drowsiness, confusion and hallucinations

Cardio= arrhythmias, HYPOTENSION (related to H2 receptor blockage in the heart)

Cimetidine= Gynecomastia and impotence in males

The H2 Blockers- “tidines”

Drug-drug Interactions

Cimetidine, Famotidine, Ranitidine are metabolized in the liver- they can cause slowing of excretion of other drugs leading to their increased concentration.

The H2 Blockers- “tidines”

Drug-drug Interactions

These drugs can interact with CIMETIDINE

Anticoagulants

Phenytoin,

Alcohol

Antidepressants.

The H2 Blockers- “tidines”

Nursing considerations:

Administer the drug WITH meals at BEDTIME to ensure therapeutic level

One hour after Antacids

Stress the importance of the continued use for the length of time prescribed

The H2 Blockers- “tidines”

Nursing considerations

Monitor the cardiovascular status especially if the drugs are given IV

Warn patient of the potential problems of increased drug concentration if the H2 blockers are used with other drugs or OTC drugs. Advise consultation first!

The H2 Blockers- “tidines”

Nursing considerations:

Provide comfort measures like analgesics for headache, assistance with ambulation and safety measures because of confusion

Warn the patients taking cimetidine that drowsiness may pose a hazard if driving or operating delicate machines.

The H2 Blockers- “tidines”

Nursing considerations:

Provide health teaching as to the dose, frequency, comfort measures to initiate when side-effects are intolerable

Evaluate the effectiveness

Relief of symptoms of ulcer, heart burn and GERD

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The Antacids

These are drugs or inorganic chemicals that have been used for years to neutralize acid in the stomach

The Antacids

The following are the common antacids that can be bought OTC:

Aluminum salts (hydroxide)

Calcium salts (carbonate)

Magnesium salts (milk of magnesia)

Sodium bicarbonate

Magaldrate (aluminum and magnesium combination)

The Antacids

Pharmacodynamics: drug action

These agents act to neutralize the acidic pH in the stomach.

They do not affect the rate of gastric acid secretion.

The Antacids

Pharmacodynamics: drug action

The administration of antacid may cause an acid rebound.

Neutralizing the stomach content to an alkaline level stimulates gastrin production to cause an increase in acid production and return the stomach to its normal acidic state.

The Antacids

Therapeutic Indications

Symptomatic relief of upset stomach associated with hyperacidity

Hyperacidic conditions like peptic ulcer, gastritis, esophagitis and hiatal hernia

Special use of AMPHOGEL (aluminum hydroxide): to BIND phosphate

The Antacids

Precautions of Antacid Use

Known allergy is a clear contraindication

Caution should be instituted if used in electrolyte imbalances, GI obstruction and renal dysfunction.

Sodium bicarbonate is rarely used because of potential systemic absorptionà metabolic alkalosis!!!

The Antacids

Pharmacokinetics

These agents are taken orally and act locally in the stomach

The Antacids

Pharmacodynamics: Effects of drugs

1. GIT= rebound acidity; alkalosis may occur.

Calcium salts may lead to hypercalcemia

Magnesium salts can cause DIARRHEA

Aluminum salts may cause CONSTIPATION and Hypophosphatemia by binding with phosphates in the GIT.

2. Fluid retention due to the high sodium content of the antacids.

The Antacids

Nursing Considerations:

Administer the antacids apart from any other medications by ONE hour before or TWO hours after- to ensure adequate absorption of the other medications

Tell the patient to CHEW the tablet thoroughly before swallowing. Follow it with one glass of water

Regularly monitor for manifestations of acid-base imbalances as well as electrolyte imbalances

The Antacids

Nursing Considerations:

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Provide comfort measures to alleviate constipation associated with aluminum and diarrhea associated with magnesium salts.

Monitor for the side-effects, effectiveness of the comfort measures, patient’s response to the medication and the effectiveness of the health teachings

The Antacids

Nursing Considerations

Evaluate for effectiveness:

Decreased symptoms of ulcer

Decreased Phosphate level (Amphogel) in patients with chronic renal failure

The PPI

These are the newer agents for ulcer treatment

The “prazoles”

Prototype: Omeprazole

Lansoprazole

Esomeprazole

Pantoprazole

The PPI

Pharmacodynamics: drug action

They act at specific secretory surface receptors to prevent the final step of acid production and thus decrease the level of acid in the stomach.

The “pump” in the parietal cell is the H-K ATPase enzyme system on the secretory surface of the gastric parietal cells

The PPI

Clinical use of the PPIs

Short-term treatment of active duodenal ulcers, GERD, erosive esophagitis and benign gastric ulcer

Long-term- maintenance therapy for healing of erosive disorders.

The PPI

Precautions with the use of the PPIs

Known allergy is a clear contraindication

Caution if patient is pregnant

The PPI

Pharmacodynamics: Adverse effects

CNS- dizziness, headache, asthenia (loss of strength), vertigo, insomnia, apathy

GIT- diarrhea, abdominal pain, nausea, vomiting, dry mouth and tongue atrophy

Respi- cough, stuffy nose, hoarseness and epistaxis.

The PPI

Nursing considerations:

Administer the drug BEFORE meals. Ensure that patient does not open, chew or crush the drug.

Provide safety measures if CNS dysfunction happens.

Arrange for a medical follow-up if symptoms are NOT resolved after 4-8 weeks of therapy.

The PPI

Nursing considerations:

Provide health teaching as to drug name, dosages and frequency, safety measures to handle common problems.

Monitor patient response to the drug, the effectiveness of the teaching plan and the measures to employ

The PPI

Nursing considerations:

Evaluate for effectiveness of the drug

Healing of peptic ulcer

Decreased symptoms of ulcer

The Mucosal Protectant

Sucralfate (Caralfate/ Iselpin)

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This is given to protect the eroded ulcer sites in the GIT from further damage by acid and digestive enzymes

Sucralfate

Pharmacodynamics: Action of drug

It forms an ulcer-adherent complex at duodenal ulcer sites, protecting the sites against acid, pepsin and bile.

This action prevents further breakdown of proteins in the area and promotes healing.

Sucralfate

Clinical use of sucralfate

Short and long term management of duodenal ulcer.

NSAIDs induced gastritis

Prevention of stress ulcer

Treatment of oral and esophageal ulcers due to radiation, chemotherapy or sclerotherapy.

Sucralfate

Precautions on the use of Sucralfate

This agent should NOT be given to any person with known allergy to the drug, and to those patients with renal failure/dialysis because of build-up of aluminum may occur if used with aluminum containing products.

The Mucosal Protectant

Pharmacodynamics: Side-effects & adverse reactions

Primarily GIT= CONSTIPATION, occasionally diarrhea, nausea, indigestion, gastric discomfort, and dry mouth may also occur

CNS= dizziness, drowsiness, vertigo

Others= rash and back pain

The Mucosal Protectant

Drug-drug interactions

If used with aluminum salts= high risk of accumulation of aluminum and toxicity.

If used with phenytoin, fluoroquinolones and penicillamines- decreased levels of these drugs when taken with sucralfate

The Mucosal Protectant

Nursing Considerations

Administer drug ON AN EMPTY stomach, 1 hour before meals , or 2 hour after meals and at BEDTIME

Monitor for side-effects like constipation and GI upset

Encourage intake of high-fiber foods and increased fluid intake

Administer antacids BETWEEN doses of sucralfate, NOT WITHIN 30 minutes of sucralfate dose

The Mucosal Protectant

Nursing Considerations

Provide comfort measures if CNS effects occur

Provide health teaching as to drug name, dosages and frequency, safety measures to handle common problems.

Monitor patient response to the drug, the effectiveness of the teaching plan and the measures employed

The Mucosal Protectant

Nursing Considerations

Evaluate effectiveness of therapy

Healing of ulcer

No formation of ulcer

Prostaglandin analogue

Misoprostol

This agent is a synthetic prostaglandin E1 analog that is employed to protect the lining of the mucosa of the stomach

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Prostaglandin analogue

Misoprostol: Pharmacodynamics

Being a prostaglandin analog, it inhibits gastric acid secretion to some degree

It INCREASES mucus production in the stomach lining.

Prostaglandin analogue

Misoprostol: Clinical use

NSAIDs-induced gastric ulcers

Duodenal ulcers unresponsive to H2 antagonists

Prostaglandin analogue

Precautions of Misoprostol Use

This drug is CONTRAINDICATED during pregnancy because it is an abortifacient.

Women should be advised to have a negative pregnancy test within 2 weeks of beginning therapy and should begin the drug on the second or third day of the next menstrual cycle.

They should be instructed in the use of contraceptives during therapy.

Prostaglandin analogue

Pharmacodynamic effects: drug reactions

GIT= Nausea, diarrhea, abdominal pain, flatulence, vomiting, dyspepsia

GU effects= miscarriages, excessive uterine CRAMPING and bleeding, spotting, hyper-menorrhea and menstrual disorders.

Prostaglandin analogue

Nursing Considerations

Administer to patients at risk for NSAIDs-induced ulcers during the full course of NSAIDs therapy

Administer four times daily with meals and at bedtime

Obtain pregnancy test within 2 weeks of beginning therapy.

Begin the therapy on second or third day of menstrual period to ensure that the woman is not pregnant

Prostaglandin analogue

Nursing Considerations

Provide patient with both written and oral information regarding the associated risks of pregnancy

Provide health teaching as to drug name, dosages and frequency, safety measures to handle common problems.

Monitor patient response to the drug, the effectiveness of the teaching plan and the measures to employ

Laxatives

Generally used to INCREASE the passage of the colonic contents

The general classifications is as follows:

1. Chemical stimulants- irritants

2. Mechanical stimulants- hyperosmotic agents and saline cathartics

3. Lubricants and stool softeners

Laxatives

They promote bowel evacuation for various purposes

They are classified into their mode of action

Laxatives

Therapeutic Indications of the Laxatives

SHORT term relief of Constipation

Prevention of straining in conditions like CHF, post-MI, post partum, post-op

Preparation for diagnostic examination

Removal of poison or toxins

Adjunct in anti-helminthic therapy

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To remove AMMONIA by use of lactulose

Contraindications in Laxative use

ACUTE abdominal disorders

Appendicitis

Diverticulitis

Ulcerative colitis

Chemical Stimulant Cathartics

Prototype: Bisacodyl

Irritant laxatives:

1. Castor oil

2. Senna

3. Cascara

4. Phenolphthalein

Chemical Stimulant Cathartics

Pharmacodynamics

These agents DIRECTLY stimulate the nerve plexus in the intestinal wall

The result is INCREASED movement or motility of the colon

Mechanical Stimulant Cathartics

Prototype: LACTULOSE (Cephulac)

Bulk-forming laxatives

1. Magnesium (citrate, hydroxide, sulfate)- saline cathartic

2. Psyllium

3. Polycarbophil

Mechanical Stimulant Cathartics

Pharmacodynamics

These agents are rapid-acting laxatives that INCREASE the GI motility by

Increasing the fluids in the colonic material

Stimulating the local stretch receptors

Activating local defecation reflex

Lubricants-Stool softener

Prototype: Docusate

1. Glycerin

2. Mineral oil

Lubricants-stool softeners

Pharmacodynamics

Docusate increases the admixture of fat and water producing a softer stool

Glycerin and Mineral oil form a slippery coat on the colonic contents

Pharmacokinetics: Common Side-effects of the Laxatives

Diarrhea

Abdominal cramping

Nausea

Fluid and electrolyte imbalance

Sympathetic reactions- sweating, palpitations, flushing and fainting

CATHARTIC dependence

The Nursing Process and Laxative

ASSESSMENT

Nursing History- elicit allergy to any laxatives, elicit history of conditions like diverticulitis and ulcerative colitis

Physical Examination- abdominal assessment

Laboratory Test: fecalysis, electrolyte levels

The Nursing Process and Laxative

NURSING DIAGNOSIS

Alteration in bowel pattern

Alteration in comfort: pain

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Knowledge deficit

The Nursing Process and Laxative

IMPLEMENTATION

1. Emphasize that it is use on a SHORT term basis

2. Provide comfort and safety measures like ready access to the bathroom, side-rails

3. Administer with a full glass of water

The Nursing Process and Laxative

IMPLEMENTATION

4. Encourage fluid intake, high fiber diet and daily exercise

5. DO NOT administer if acute abdominal condition like appendicitis is present

6. Advise to change position slowly and avoid hazardous activities because of potential dizziness

The Nursing Process and Laxative

IMPLEMENTATION

7. Record intake and output to assess fluid alteration

8. If possible, observe the character of stools

9. Caution the patient that chronic use may promote dependence and use during pregnancy may cause uterine cramping and Vitamin deficiency

The Nursing Process and Laxative

EVALUATION of drug effectiveness

1. Evaluate relief of GI symptoms, absence of staining and increased evacuation of GI tract

2. For Lactulose: decreased ammonia

3. Normal bowel function is restored

The Anti-diarrheals

These are agents used to calm the irritation of the GIT for the symptomatic relief of diarrhea

General Classifications

1. Local anti-motility

2. Local reflex inhibition

3. Central action on the CNS

The Anti-diarrheals

Clinical Indications of drug use

Relief of symptoms of acute and chronic diarrhea

Reduction of fecal volume discharges from ileostomies

Prevention and treatment of traveler's diarrhea

Contraindications of anti-diarrheal Use

Poisoning

Drug allergy

GI obstruction

Acute abdominal conditions

Pharmacokinetics: Side effects

Constipation

Nausea, vomiting

Abdominal distention and discomfort

TOXIC MEGACOLON

Nursing process and anti-diarrheals

ASSESSMENT

Nursing History – Elicit history of drug allergy, conditions like poisoning, GI obstruction and acute abdominal conditions

Physical Examination- Abdominal examination

Laboratory test- electrolyte levels

Nursing process and anti-diarrheals

NURSING DIAGNOSIS

Alteration in bowel pattern

Alteration in comfort: pain

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Nursing process and anti-diarrheals

IMPLEMENTATION

1. Monitor patient response within 48 hours. Discontinue drug use if no effect

2. Provide comfort measures for pain

3. Provide teaching regarding its short term use only

Nursing process and anti-diarrheals

EVALUATION

1. Monitor effectiveness of drug- RELIEF of diarrhea

2. Monitor adverse effects, effectiveness of pain measures and effectiveness of teaching plan

Emetics and Anti-emetics

Emetic Agent

Syrup of Ipecac

Anti-emetics

1. Phenothiazines

2. Non-phenothiazines

3. Anticholinergics/Antihistamines

4. Serotonin receptor Blockers

5. Miscellaneous

EMETIC

Prototype: Ipecac Syrup

EMETIC

Pharmacodynamics

Ipecac syrup irritates the GI mucosa locally, resulting to stimulation of the vomiting center

It acts within 20 minutes

EMETIC

Clinical Use of ipecac

To induce vomiting as a treatment for drug overdose and certain poisonings

EMETIC

Contraindications of Ipecac use

Ingestion of CORROSIVE chemicals

Ingestion of petroleum products

Unconscious and convulsing patient

EMETIC

Pharmacokinetics: side effects of Ipecac

Nausea

Diarrhea

GI upset

Mild CNS depression

CARDIOTOXICITY if large amounts are absorbed in the body

Nursing process and the EMETIC

ASSESSMENT

Nursing History- elicit the exact nature of poisoning

Physical Examination- CNS status and abdominal exam

Nursing process and the EMETIC

IMPLEMENTATION

1. Administer to conscious patient only

2. Administer ipecac as soon as possible

3. Administer with a large amount of water

4. Vomiting should occur within 20 minutes of the first dose. Repeat the dose and expect vomiting to occur within 20 minutes

Nursing process and the EMETIC

IMPLEMENTATION

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5. Provide comfort measures like ready access to bathroom, assistance with ambulation

6. Offer support

Nursing process and the EMETIC

EVALUATION

1. Evaluate patient response within 20 minutes of drug ingestion

2. Monitor for adverse effects

3. Evaluate effectiveness of comfort measures and teaching plan

ANTI-EMETICS

These are agents used to manage nausea and vomiting

They act either locally or centrally

In general, they may inhibit the chemoreceptor trigger zone in the medulla by blocking DOPAMINE receptor

ANTIEMETICS

ANTIEMETICS

ANTIEMETICS

ANTIEMETICS

Indications

1. Prevention and treatment of vomiting

2. Motion sickness

ANTIEMETICS

Contraindications

1. Severe CNS depression

2. Severe liver dysfunction

ANTIEMETICS

Pharmacokinetics:

Oral absorption is good if vomiting is not present

IV drugs can be given if vomiting is active

Most drugs are metabolized in the liver excreted in the kidneys

ANTIEMETICS

Pharmacokinetics: Side-effects

1. PHOTHOSENSITIVITY

2. Drowsiness, dizziness, weakness and tremors and DEHYDRATON

3. Phenothiazines= autonomic anti-cholinergic effects like dry mouth, nasal congestion and urinary retention

Metoclopramide= EPS due to dopamine receptor blockage

Nursing Process and the ANTIEMETICS

ASSESSMENT

Nursing History- elicit allergy, impaired hepatic function and CNS depression

Physical Examination- CNS status and abdominal examination

Laboratory test- Liver function studies

Nursing Process and the ANTIEMETICS

NURSING DIAGNOSIS

1. Alteration in comfort: pain

2. High risk for injury

3. Knowledge deficit

Nursing Process and the ANTIEMETICS

IMPLEMENTATION

1. Assess patient’s intake of other drugs that may cause dangerous drug interaction

2. Emphasize that this is given on a short term basis

Nursing Process and the ANTIEMETICS

IMPLEMENTATION

3. Provide comfort and safety measures

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Advise to change position slowly

Avoid hazardous activities

Provide mouth care and ice chips

Monitor for dehydration and offer fluids if it occurs

Nursing Process and the ANTIEMETICS

IMPLEMENTATION

4. Protect from sun exposure

Sunscreens

Protective covering

5. Provide health teaching

Nursing Process and the ANTIEMETICS

EVALUATION

1. Monitor for the drug effectiveness

• Relief of nausea and vomiting

2. Monitor for adverse effects

3. Evaluate effectiveness of comfort measures and teaching plan

CENTRAL NERVOUS SYSTEM DRUGS

CNS STIMULANTS: Overview

A. Description

- an effect that may be noted with use of many drugs

- actual indications for using CNS is limited

- includes amphetamines and amphetamine-like agents

B. Action

- stimulants enhance neurotransmitter activity in the CNS, particularly the cerebral cortex

- produces peripheral effects on BP, GI motility, vasoconstriction and pupillary dilation

C. Indications

- treatment of Narcolepsy

- treatment of attention deficit disorder with hyperactivity in children

- exogenous obesity

D. Overview of nursing interventions

- be aware that nursing interventions will vary depending on the intended effect

- provide client teaching based on the indication for using the drug

- note that the least amount possible of the drug should be prescribed at one time to minimize the possibility of overdosage

CNS STIMULANTS

CNS stimulants tend to produce an effect that increases energy or reduces fatique and associated symptoms

PHARMACODYNAMICS/ACTION

1. cause release of norepinephrine from its storage sites in adrenergic nerve terminals

2. effects of these agents may be similar to those of ephedrine

PHARMACOTHERAPEUTICS

- varies according to indications

PHARMACOKINETICS

1. most CNS stimulants are absorbed through the GI system

2. duration of action is variable

3. excretion occurs through the kidney

CONTRAINDICATIONS

1. in clients with symptomatic CV disease, hyperthyroidism, nephritis, angina pectoris, moderate to severe hypertension, types of glaucoma, and history of drug abuse

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2. used caution in clients with DM or seizure disorders, in elderly, hyperexcitable clients

DRUG INTERACTIONS

- vary among specific drugs

NURSING MANAGEMENT:

ASSESSMENT

a. assess client hx of drug abuse

b. review the complete history and physical examination

PLANNING AND IMPLEMENTATION

a. Monitor height and weight in children

b. Monitor for s/sx of Tourettes syndrome in children

c. When used as “anorectic “ in obese, make sure client is on a weight reduction program. Give 30 to 60 minutes before meals

d. Explain to client the reason, what to expect, and dangers of this drugs

e. Tell the client to avoid caffeine containing drinks

f. Warn the client to avoid activities that require alertness

h. Instruct client to take 6 hours before bedtime to avoid sleep interference

i. Inform client that as drug wears off, fatigue may result

COMMON CNS stimulants:

I. AMPHETAMINE SULFATE

ACTION – in children with hyperkinesia

CONTRAINDICATIONS

a. In clients with parkinsonism

b. Contraindicated within 14 days of MAO inhibitors

DRUG INTERACTIONS:

- ammonium chloride, ascorbic acid

- antacids, sodium bicarbonate, acetazolamide

- antihypertensives

- caffeine

- haloperidol, phenothiazine, tricyclic antidepressants

- insulin, oral antidiabetic

- ammonium chloride

- bicarbonate

NURSING MANAGEMENT:

a. be aware that high doses can result in acute psychotic picture

b. know that amphetamines are subject to abuse, that leads to compulsive behavior, paranoia, hallucinations and suicidal tendencies

c. be aware for the street names ( black beauties, lid poppers, pep pills and speed)

d. note that amphetamines should only be used in weight reduction programs for clients in whom alternate therapy has been ineffective

II. DEXTROAMPHETAMINE (DEXEDRINE)

- related both chemical and pharmacologic to norepinephrine

- peak occurs within 4 to 6 hours

- elimination half-life is about 5 hours

- metabolized in the liver and excreted in the urine

- drug interations: same as for amphetamine

- side/adverse effects: same as for amphetamine

III. METHAMPHETAMINE HYDROCHLORIDE ( DESOXYN)

- like dextroamphetamine related to norepinephrine. It is often referred to as “speed”

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- pharmacokinetics: same as for dextroamphetamine

- used with caution in clients with hypertension

IV. DIETHYLPROPION HYDROCHLORIDE (TENUATE)

- an anorexiant

- half-life 4 to 6 hrs; effects of regular-release tablets persist for 4 hours; effects of extended-release tablets and capsules can last for 12 hours

- short term adjunct in exogenous obesity

- suppressing the appetite

V. PHENTERMINE (IONAMINE)

- used along with Fenfluramine as diet aid; known as the “phen/fen diet”

- less potent action in the CNS than most amphetamines, with little stimulation of the CV system

- duration of action is prolonged and may last up to 20 hours.

ANALGESICS

A. OPIODS

- symptomatic relief of severe acute and chronic pain

- most commonly used in the postoperative setting and to treat pain caused by malignancy

- produce effects by binding to opioid receptors throughout the CNS and peripheral tissues

- onset of action is immediate if given by IV and rapid if given by IM or by mouth

- peak action is from 1 to 2 hours and duration up to 7 hours

- these agents cross the BBB and placental barriers and also into breast milk

- may increase intracranial pressure

- causes anorexia

NURSING CONSIDERATIONS:

1. assess pain for type, intensity and location

2. assess VS especially the RR (<12 bpm withhold)

3. assess for CNS changes including LOC

4. assess client for allergic reaction

5. assess older adults frequently

CLIENT EDUCATION:

1. avoid alcohol and other CNS depressants

2. not over the counter

3. avoid ambulation, smoking, driving and other activities without assistance

4. report any changes such as allergic reactions or shortness of breath

5. long-term use can lead to withdrawal symptoms with termination of use

COMMON OPIOID ANALGESICS:

Pure agonist – Codeine (Paveral)

- IM and PO

- Meperidine (Demerol)

- PO, IM, IV, SubQ

- Morphine Sulfate

- PO, IV

- sevre pain, short acting

Mixed agonists-antagonist

- Nalbuphine hydrochloride (Nubain)

- IM, IV, SubQ, IV

- limited use for severe and chronic pain

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b. OPIOID ANTAGONIST

- include Naloxone (Narcan) and Naltrexone (ReVia)

- used to reverse respiratory depression induced by overdose of opioids

- onset of effect 1-2 minutes, duration 45 minutes

NURSING CONSIDERATIONS:

1. assess VS q 3-5 minutes

2. assess ABG

3. assess cardiac status

4. assess RR and LOC

5. administer only with resuscitative device nearby

c. NON-OPIOIDS

1. ACETYLSALICYLIC ACID (ASPIRIN)

- inhibits prostaglandin involved in the production of inflammation, pain and fever

- blocks pain impulses in CNS

- antipyretic action results from vasodilatation of peripheral vessels

- inhibits platelet aggregation

- dosage varies depending on age of client

- gastric irritation may be decreased by administering with full glass of water, milk, food or antacid

- pills can be crushed or chewed but do not crush enteric-coated preparations

- give 30 minutes prior to or 2 hours following meals

- contraindicated in children < 12 y/o because of risk of Reye’s syndrome, children w/ chicken pox or flu-like symptoms, pregnacy 3rd trimester, lactation

- contraindicated with Vitamin K deficiency, PUD, anemia, renal and hepatic dysfunction

NURSING CONSIDERATIONS:

1. assess for allergy to salicylates

2. assess liver functions tests, renal function tests (BUN,Crea) and blood studies (CBC, Hct, Hgb, PT)

3. assess for hepatotoxicity

( dark urine, clay-colored stool, jaundice, itching)

4. note for abdominal pain, fever, diarrhea

5. evaluate for therapeutic responses

6. assess for aspirin toxicity when administered with ammonium chloride

CLIENT TEACHING:

1. report any symptoms of hepatotoxicity or renal toxicity

2. report visual changes, tinnitus, allergic reactions, and bleeding

3. take medication with 8 oz water, milk or food

4. do no exceed recommended dose

5. do not combine with other OTC medications containing ASA

6. therapeutic response can take up to 2 weeks

7. avoid alcohol ingestion to decrease chance of GI bleeding

8. should not be given to children or teens with flu-like symptoms or chicken pox

2. ACETAMINOPHEN (TYLENOL)

- inhibition to prostaglandin synthesis

- possess weak anti-inflammatory properties

- more on anti-pyretic action

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- used to mild to moderate pain or fever, especially when ASA or NSAIDs are not tolerated

- usual dose is 325 to 600 mg q4-6h PO or PR, maximum dose is 4 grams per day

- oral forms may crushed or given as whole or chewable tablets

- may give with food or milk to increase gastric tolerance

- co-administration with high-carbohydrate meal with significantly retard absorption rate

- hepatotoxicity

- cyanosis, anemia, neutropenia, jaundice, pancytopenia, CNS stimulation, delirium

NURSING CONSIDERATIONS:

1. assess client for chronic poisoning (rapid, weak pulse, dyspnea, cold, clammy extremities)

2. assess for hepatotoxicity

3. be prepared to administer ACETYLCYSTEINE (MUCOMYST) as antidote for acetaminophen poisoning

3. NONSTEROIDAL ANTIINFLAMMATORY DRUGS (NSAIDs)

- inhibit cyclooxygenase and decrease prostaglandins and thromboxane

- used to treat mild to moderate pain, osteoarthritis and dysmenorrhea

- gastric irritants

- crushed or chewed (Pills only)

- give 30 minutes prior to or 2 hours following meals for best absorption

NURSING CONSIDERATIONS:

1. assess for renal and hepatic function

2. audiometric, ophthalmic exam before, during, and after treatment

3. assess for ear and eye problems

CLIENT EDUCATION:

1. report blurred vision, ringing, roaring in ears which may indicate toxicity

2. avoid driving or other hazardous activities

3. report changes in urine pattern, increased weight, edema, increased pain in joints, fever, blood in urine indicating nephrotoxicity

COMMON NSAIDs AGENTS:

1. Celecoxib (Celebrex)

- PO

- decreases effect of ASA, ACE inhibitors, diuretics

2. Diclofenac sodium (Voltaren)

- PO

3. Ibuprofen (Advil)

- PO

4. Ketorolac (Toradol)

- IV, IM, PO

5. Mefenamic Acid (Ponstan)

- PO

6. Naproxen (Naprosyn)

- PO

7. Piroxicam (Feldene)

- PO

ANTICONVULSANTS AGENT

- These agents include hydantoins, iminostillbenes, succinimides, valproic acid

- Suppress seizure activity by altering ionic conductance, neuronal membrane potentials and the level of certain neurotransmitters

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- Management and control of partial and generalized seizures that are idiopathic or unresponsive to other interventions

- There are no contraindications to anti-epileptic use

- teratogenecity: Fetal hydantoin syndrome has been associated with antiepileptic use in pregnancy (specifically phenytoin or other hydantoin drugs)

HYDANTOINS

- suppress sodium influx across neuronal cell membranes

- inhibit the spread of seizure activity in the motor cortex

- used in general toni-clonic (grand mal), status epilepticus, pyschomotor seizures (complex focal seizures)

- do not interchange chewable phenytoin products with capsules

- phenytoin readily binds with protein

- give ethosuximide, diazepam, and carbamazepine with food or milk to reduce GI symptoms

- significant food interactions: Phenytoin absorption is decreased by enteral nutrition products

- paresthesias, nystagmus, diplopia, gingival hyperplasia

- Steven-Johnson syndrome

NURSING CONSIDERATIONS:

1. assess for seizure activity including type, location, duration, and character

2. assess mental status, mood, sensorium, affect and memory

3. assess for respiratory depression, rate, depth and character

4. administer dose with food to reduce risk of GI upset

CLIENT EDUCATION:

1. medication regimen (name, dose, schedule, SE, and possible adverse effects)

2. urine may turn pink

3. do not discontinue abruptly or without consulting physician

4. brush teeth with soft toothbrush and do proper flossing to prevent gingival hyperplasia

5. avoid heavy used of alcohol

BARBITURATES

- decrease impulse transmission to the cerebral cortex

- used in all forms of epilepsy

- give oral dose on empty stomach

- administer IM injection into large muscle mass to prevent tissue sloughing

SUCCINIMIDES

- suppress Calcium influx into neurons, inceasing the electrical threshold and decreasing ability to generate an action potential

- used in absence seizures, partial and tonic-clonic

NURSING CONSIDERATIONS:

1. Monitor renal studies including UA, BUN and creatinine

2. Assess for eye problems

3. Monitor weight weekly

BENZODIAZEPINES

- enhance the inhibitory neurotransmitter GABA to decrease anxiety and as an adjunct for seizure activity

- give with food or milk

- IV injection should be given into large vein

- contraindicated in acute narrow angle glaucoma

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- contraindicated in children younger than 6 months

- do not give to clients w/ liver disease (clonazepam) or during lactation ( diazepam)

NURSING CONSIDERATIONS:

1. assess BP, pulse if systolic BP drops 20mmHg withhold then notify physician

2. assess hepatic and renal function

3. advice to use barrier contraceptives while taking this drugs

Other antiepileptics:

1. CARBAMAZEPINE (TEGRETOL)

- inhibits nerve impulse by limiting influx of sodium ions across cell membrane in motor cortex

- used in tonic-clonic, complex partial and mixed seizures

- give oral forms with food and milk

- contraindicated with bone marrow depression

2. VALPROATES

- increases levels of GABA in brain, which decreases seizure activity

- given by the oral or enteral (GI tube) route

ANTIPYSCHOTICS

A. PHENOTHIAZINES

- neuroleptics

- also known as typical antipsychotic agents

- predominantly dopamine antagonists thus they block postsynaptic dopamine2 receptors in several DA in the brain

- typical antipsychotics are most effective in treating the “positive” symptoms but are less effective in the “negative” symptoms

- tolerance to antipsychotic medications is very uncommon

- most toxic drugs used in psychiatry

a. CHLORPROMAZINE (THORAZINE)

- used primarily to treat psychotic disorders

- 3 goals:

1. suppression of acute episodes

2. prevention of acute exacerbations

3. maintenance of the highest possible level of functioning

- effects can usually be seen in 1-2 days but substantial improvement usually takes 2-4 weeks and full effects into months

AUTONOMIC NERVOUS SYSTEM

CHOLINERGIC DRUGS

These drugs promote the action of neurotransmitter acetylcholine

Also called parasympathomimetic drugs ( because they produce effects that imitate parasympathetic nerve stimulation

Two major classes of cholinergic drugs:

a. cholinergic agonist – mimic the action of the neurotransmitter acetylcholine

b. anticholinesterase drugs – work by inhibiting the destruction of acetylcholine at cholinergic receptor sites

How cholinergic drugs work..

Cholinergic agonist

When a neuron in the PNS is stimulated, the neurotransmitter Ach is released. Ach crosses the synapse and interacts with receptors in the adjacent neuron. Cholinergic agonist drugs work by stimulating cholinergic receptors, mimicking the action of Ach.

Anticholinesterase drugs

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After Ach stimulates the cholinergic receptor, it’s destroyed by the enzyme acetylcholinesterase. Anticholinesterase drugs produce their effects by inhibiting acetylcholinesterase. As a result, Ach isn’t broken down and begins to accumulate; therefore, the effects of Ach are prolonged.

CHOLINERGIC AGONIST

Directly stimulating cholinergic receptors, cholinergic agonists mimic the action of the neurotransmitter acetylcholine

Example:

Acetylcholine Cevimeline

Pilocarpine Pilocarpine

Betanechol

Carbachol

Pharmacokinetics

- Depend on the affinity of the individual drug for muscarinic or nicotinic receptors

- For example, the drug acetylcholine poorly penetrates the CNS

- Usually administered: topically, with eye drops

orally

subcutaneous injection

( more rapidly than oral)

- Rarely administered by IM or IV

( because they’re almost immediately broken down by cholinesterase in the interstitial spaces between tissues and inside the blood vessels)

( begin to work rapidly and can cause cholinergic crisis)

- Cholinergic agonist are absorbed rapidly and reach peak levels within 2 hours

- Food decreases their absorption

- Less than 20% is protein bound

Summed up:

- All cholinergic agonist are metabolize by cholinesterase:

1. at the muscarinic and nicotinic receptor sites

2. in the plasma ( the liquid portion of the blood)

3. in the liver

- Excreted by the kidneys

Pharmacodynamics

- Works by mimicking the action of acetylcholine on the neurons in certain organs of the body called the target organs

- They stimulate the muscle and produce:

salivationbradycardia

dilation of BV constriction of pulmonary

increase GI tract increased tone & contraction

of the bladder

constriction of the pupils

Pharmacotherapeutics

- Treat atonic (weak) bladder conditions and postoperative and postpartum urine retention

- Treat GI disorders, such as postoperative abdominal distention and GI atony

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- Reduce eye pressure in patients with glaucoma and during eye surgery

- Treat salivary gland hypofunction

Drug interactions

- Other cholinergic drugs, especially anticholinesterase drugs (ambenopium, edrophonium, neostigmine) boost the effects of cholinergic agonist and increase the risk of toxicity

- Anticholinergic drugs

- Quinidine reduces the effectiveness of cholinergic agomist

Assessment:

1. Assess for disorders in which cholinergic agonist are used such as Myasthenia gravis

2. Assess for urine retention and bladder distention; determine the patients fluid intake , time and amount of last urination

3. Assess for possible paralytic ileus ( check for bowel sounds, abdominal distention and determine the patients elimination pattern)

4. Assess for disorders that may be aggravated by cholinergic agonist (Alzheimers dse.)

Implementation:

1. Administer cholinergic drugs as prescribed

2. Be aware that some drugs, such as Bethanechol should be given before meals

3. Monitor for effects of cholinergic drugs and report adverse reactions( nausea, vomiting, cramps, diarrhea, blurring of vision)

4. Assess for respiratory adequacy

5. Assess for urinary adequacy and signs of urine retention

Health teachings:

1. Take the drug as directed on a regular schedule to maintain consistent blood levels of the drug and symptom control

2. Don’t chew or crush sustained-release tablets or capsules

3. Take oral cholinergics on an empty stomach

4. If diarrhea or vomiting occurs, ensure adequate fluid intake

5. Cholinergic drugs act within 60 minutes. Make sure bathroom facilities are available.

6. If taking in long term mode, wear or carry medical alert identification

7. For those with MG, plan rest periods between activities and space activities throughout the day

8. Report increased muscle weakness, difficulty breathing, recurrence of MG symptoms

Anticholinesterase drugs

Block the action of the enzyme acetylcholinesterase at cholinergic receptor site

Preventing the breakdown of the neurotransmitter acetylcholine

As Ach builds up, it continues to stimulate the cholinergic receptors

Divided into 2 categories: Reversible and Irreversible

Reversible (short acting)

Ambenonium

Donepezil

Edrophonium

Neostigmine

Physostigmine

Rivastigmine

Tacrine

Irreversible (long acting)

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Used primarily as toxic insecticides and pesticides or as nerve gas agents in chemical warfare

Echothiopate

Pharmacokinetics

- Readily absorbed from the GI tract, subcutaneaous tissue and mucous membrane

- Because neostigmine is poorly absorbed from the GI tract, the patient needs a higher dose when taking this drug orally

- When a rapid effect is needed, the drug should be given in IM or IV route

- Distribution varies

- example: Physostigmine – cross the BBB

Donepezil – highly bound to plasma

CHON

Tacrine – about 55% bound

Rivastigmine – 40% bound

Galantamine – 18% bound

- Metabolized in the body by enzymes in the plasma and excreted in the urine

- Donepezil, Galantamine, Rivastigmine, and Tacrine are metabolized in the liver but still excreted in urine

Pharmacodynamics

- Promote the action of acetylcholine receptor sites

- They can produce a stimulant or depressant effect on cholinergic receptors

- Reversible – block the breakdown of acetylcholine for minutes to hours

- Irreversible – can last for days or weeks

Pharmacotherapeutics

1. To reduce eye pressure

2. To increase bladder tone

3. To improve tone and peristalsis through the GI tract in patients with reduced motility and paralytic ileus

4. To promote muscular contraction in patients with MG

5. To diagnosed MG

6. As antidotes to anticholenergic drugs, tricyclic antidepressants

7. To treat mild to moderate dementia and enhance cognition in patients with Alzheimers dse.

Drug Interactions

- Other cholinergic agonist, particularly cholinergic agonist ( bethanechol, carbachol, pilocarpine)

- Carbamazepine, dexamethasone, rifampicin, phenytoin and phenobarbital

- Aminoglycosides antibiotics, anesthetics and anticholinergic drugs

- Inhibitors of cytochrome P450 ( cimetidine and erythromycin)

- Cigarette used

Adverse Reactions

- Increased action of Ach at receptor sites

- Cardiac arrhythmias, nausea and vomiting, diarrhea, SOB, wheezing, seizures, headache, anorexia, insomnia, pruritus, urinary frequency and nocturia

Assessment:

1. Assess for disorders in which anticholinesterase drugs are used, such as MG, alzheimers, glaucoma and altered bladder function

2. Assess for urine retention and bladder distention, determine the patient’s fluid intake,

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and find out the time and amount of his last urination

3. Assess for possible paralytic ileus by checking for BS and abdominal distention and determining the patients elimination pattern

Anticholinergic drugs

- Interrupt parasympathetic nerve impulses in the CNS and ANS

- Prevent Ach from stimulating cholinergic receptors

- Don’t block all cholinergic receptors, just the muscarinic receptors sites

Belladonna Alkaloids

- Atropine

- Belladona

- Homatropine

- Hyocyamine

- Scopolamine

Synthetic derivatives of belladonna alkaloids

(quarternary ammonium drugs)

- Glycopyrrolate

- Methscopolamine

- Propantheline

Tertiary amines – newer synthetic drugs

- Centrally acting and more selective

- Fewer side effects

- Benztropine, Dicyclomine, Oxybutynin, Tolterodine, Trihexyphenidyl

Pharmacokinetics

- Belladonna alkaloids are absorbed from the eyes, GI tract, mucous membranes, and skin

- Quarternary ammonium drugs and tertiary amines are absorbed primarily through the GIT

- Belladona class are distributed more widely throughout the body

- Alkaloids readily cross the BBB

- Belladonna metabolized in the liver and excreted in the kidneys

- Metabolism of tertiary amines is unknown, but excretion is usually through the kidneys and feces

- Quarternary ammonium drugs are bit more complicated, hydrolysis occurs in the GIT and liver, excretion is n feces and urine

Pharmacodynamics

- Produces paradoxical effect (depending on the dosage, condition being treated and target oragn)

- Example: in the brain they can produce a stimulating and depressing effect

- Example: Parkinson’s dse, characterized by low dopamine levels that intensify the stimulating effects of Ach, cholinergic blcokers depress this effect

Pharmacotherapeutics

- anticholinergic drugs are used in various GI situations

1. all anticholinergic drugs are used to treat spastic or hyperactive conditions of the GI and urinary tracts

- for bladder relaxation and urinary incontinence, quarternary ammonium compounds (propantheline) drug of choice because of fewer adverse effects

2. the belladonna alkaloids are used with morphine to treat biliary colic

3. given by injection before some diagnostic procedures to relax the GI smooth muscles

Drug Interactions

- Drugs that increase the effects of anticholinergic drugs include:

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1. antidyskinetics ( amantadine)

2. antiemetics and antivertigo drugs ( meclizine)

3. antipsychotics (haloperidol)

4. cyclobenzaprine

5. tricyclic and tetracyclic antidepressants

Adverse Reactions

- Dry mouth, reduced bronchial secretions, increased heart rate, blurred vision, decreased sweating

Assessment

- Assess for conditions in which anticholinergic drugs would be used, such as bradycardia, heart block, diarrhea and PUD

- Assess for conditions in which anticholinergic drugs would be contraindicated ( glaucoma, MG, prostatic hyperplasia, reflux esophagitis, GI obstructive dse)

Implementation

1. Follow dosage recommendations, some drugs should be given with meal

2. Monitor VS, cardiac rhythm, UO, and vision for potential drug toxicity

3. Monitor for adverse reactions (dry mouth, inc heart rate and blurred vision)

Adrenergic drugs

- Also called sympathomimetic drugs

- Classified into two groups based on their chemical structure: cathecolamines and noncatecholamines

- Also divided by action:

1. direct acting – acts directly on the organ or tissue innervated by SNS

2. indirect acting – in which the drug triggers the release of neurotransmitters (norepinephrine)

3. dual acting - both

Catecholamines

- They stimulate the nervous system, constrict peripheral blood vessels, increase heart rate and dilate the bronchi

- Common examples:

dobutamine dopamineepinephrine

norepinephrine

isoproterenol Hcl/sulfate

Pharmacokinetics

- can’t be take orally (destroyed by digestive enzymes)

- In contrast, when these drugs are given sublingually, rapidly absorbed though the mucous membrane

- SC absorption is slowed ( cause the BV around the injection site to constrict)

- IM faster because of less constriction

- Metabolized and inactivated predominantly in the liver ( GIT, lungs, kidneys, plasma, tissues)

- Excreted primarily in the urine ( isoproterenol – feces, epinephrine – breast milk)

Pharmacodynamics

- Primarily direct acting

- Combine with alpha-adrenergic or beta-adrenergic receptors

- Cause either excitatory and inhibitory

- Alpha-adrenergic – excitatory response except for intestinal relaxation

- Beta-adrenergic – inhibitory except in the cells of the heart

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Pharmacotherapeutics

- Most adrenergics produce their effects by stimulating alpha and beta adrenergic receptors

- Norepinephrine has the most nearly pure alpha activity

- Dobutamine and isoproterenol have only beta therapeutic use

- Epinephrine stimulates alpha and beta

- Dopamine primarily exhibits dopaminergic activity

- Cathecholamines that stimulate alpha-adrenergic are used to treat hypotension ( loss of vasomotor tone, blood loss

- Cathecolamines that stimulate beta1-adrenergic are used to treat bradycardia, heart block, low cardiac output, ventricular fibrillation, asystole, cardiac arrest

- Cathecolamines that exert beta2-adrenergic activity are used to: acute and chronic bronchial asthma, emphysema, bronchitis, acute hypersensitivity

- Dopamine is used in low doses to improve blood flow to the kidneys (it dilates the renal blood vessels)

Drug Interactions:

Alpha-adrenergic blockers (phentolamine) – can produce hypotension

Epinephrine – may cause hyperglycemia

Beta-adrenergic blockers (propanolol) – can lead to brochial constriction

Tricyclic antidepressants – can lead to hypertension

Adverse reactions:

- Palpitations

- Cardiac arrhtyhmias

- Hypotension

- Hypertension and hypertensive crisis

- Increased glucose levels

- Tissue necrosis and sloughing

Assessment:

1. Assess the pt.’s condition before tx

2. Continuously monitor ECG, BP, PAWP, cardiac condition, UO

3. Monitor electrolyte levels

4. After dopamine is stopped, watch closely for a sudden drop in BP

Implementation:

1. Before starting catecholamines, correct hypovolemia with plasma volume expanders

2. Give cardiac glycosides before cathecolamines; cardiac glycosides increase AV node conductions and patients with AF may develop rapid ventricular rate

3. Administer drug using central venous catheter or large peripheral vein

4. Dilute the concentrate for injection before administration

5. Watch for irritation and infiltration; extravasation can cause an inflammatory response

6. Don’t give cathecolamines in the same IV line as other drugs (beware of incompatibilities)

ex. Dobutamine – heparin, hydrocortisone sodium

succinate, cefasolin, penicillin

7. Don’t mix dobutamine or dopamine with sodium bicarbonate injection or phenytoin ( incompatible with alkaline solutions)

8. Change IV sites regularly to avoid phlebitis

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9. Provide patient teaching

Noncathecolamines

- Many therapeutic uses because of the various effects these drugs can have on the body including:

1. local and systemic constriction of blood vessels (phenylephrine)

2. nasal and eye decongestion and dilation of the bronchioles ( albuterol, bitolterol, ephedrine, formoterol, isoetharine Hcl, terbutaline)

3. smooth muscle relaxation (terbutaline)

Pharmacokinetics:

- Depends on the route of administration

1. inhaled drugs (albuterol) – gradually absorbed from the bronchi thus resulting in lower drug levels in the body

2. oral drugs – absorbed well from the GI tract and are distributed widely in the body fluids and tissues

3. some crosses the BBB (ephedrine)

- Metabolism and inactivation of noncathecolamines occur primarily in the liver but also in the lungs, GIT and other tissues

- Excreted primarily in the urine

- Inhaled albuterol are excreted within 24 hours

- Oral albuterol – within 3 days

- Acidic urine increases excretion of many noncathecolamines, alkaline urine slows excretion

Pharmacodynamics:

- Noncathecolamines can be direct-acting, indirect or dual ( unlike cathecolamines, primarily direct-acting)

1. direct-acting noncathecolamines – stimulate alpha activity receptors including phenylephrine. Those that selectively stimulate

beta2 activity receptors (albuterol, isoetharine, metaproterenol, terbutaline)

2. indirect-acting noncathecolamines – exert their effect by indirect action on adrenergic receptors

3. dual acting – ephedrine and mephentermine

Pharmacotherapeutics:

- Stimulate SNS and produce various effects on the body

1. mephentermine – causes vasoconstriction and is used to treat hypotension in severe shock

2. terbutaline – used to stop in preterm labor

Drug interactions:

- Anesthetics – can cause arrthymias and hypotension

- Monoamine oxidase inhibitors – severe hypertension

- Tricyclic antidepressants – cause hypertension and arrthymias

- Urine alkalizers ( acetazolamide and Na bicarb) – can cause slow excretion

Assessment:

- Obtain a baseline assessment of the pt’s respiratoty status, and assess it frequently throughtout therapy

- Assess for adverse reactions and drug interactions

- Assess the pt’s and family’s knowledge of the drug therapy

Adrenergic blocking drugs

- Also called sympatholytic drugs

- Used to disrupt SNS

- Their action at these sites can be exerted by:

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1. interrupting the action of adrenergic drugs

2. reducing available NE

3. preventing the action of cholinergic drugs

- Classified according to their site of action as:

1. alpha-adrenergic blockers (alpha blockers)

2. beta-adrenergic blockers ( beta blockers)

Alpha-adrenergic blockers

- Work by interrupting the actions of the cathecolamines ( E and NE) at alpha receptors

- This results in:

1. relaxation of the smooth muscle in the blood vessels

2. decreased blood pressure

- Drugs in this class includes:

ergoloid mesylates ergotamine

phenoxybenzamine phentolamine

terazosindoxazosin

prazosin

Pharmacotherapeutics:

- Hypertension

- Peripheral vascular disorder

- Pheochromocytoma

- Vascular headache

Implementation:

1. Give drugs at bedtime

2. Begin tx with small dose to avoid syncope

3. Don’t give sublingual tablets with food or drink

4. Provide patient teaching

Beta-adrenergic blockers

- Most widely used adrenergic blockers

- Prevent stimulation of the SNS by inhibiting the action of cathecolamines at beta adrenergic receptors

- Beta-adrenergic blockers are selective or nonselective beta-adrenergic blockers affect:

1. beta1 receptors site (heart)

2. beta2 receptor site (bronchi, BV and uterus)

Nonselective:

*Carvedilol

*Labetalol

- Levobunolol

- Penbutolol

- Pindolol

- Propanolol

* Also block alpha1 receptors

Selective:

- Acebutolol

- Atenolol

- Betaxolol

- Bisoprolol

- Esmolol

- metoprolol

Pharmacokinetics:

- Usually absorbed rapidly from the GIT

- Protein bound to some extent

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- Distributed widely in body tissues, with the highest concentrations found in the heart, liver, lungs and saliva

- Nadolol and atenolol – urine, feces and breastmilk

- Metabolized in the liver

Pharmacotherapeutics:

- Can be prescribed after a heart attack to prevent another heart attack or to treat:

1. angina

2. hypertension

3. hypertrophic cardiomyopathy

4. SV arrhythmias

Assessment:

- Assess respiratory status (COPD or asthma because of potential vasospasm)

- Check apical pulse rate ( alert the prescriber if pulse rate is below 60bpm)

- Monitor BP, ECG, HRR ( be alert for progression of AV block or bradycardia)

Nursing Pharmacology

Anti- Neoplastic

Chemotherapeutic Drugs

General Description

These agents kill or inhibit the reproduction of neoplastic cells

They may be cycle specific or non specific

They are used in combination, or with other treatment modalities

Usull given IV

Undesirable effects

“BARFS”

Bone Marrow Depression

Alopecia

Retching- Nausea and Vomiting

Fear and Anxiety

Stomatitis

General Guidelines for Anti-Neoplastic Agents

CBC and Platelets monitoring

Anti-emetics are given BEFORE drug

NEPHROTOXICITY is an important Side effect

Counseling regarding reproductive issues

Encourage hand washing and avoidance of crowds

Recommend wig for alopecia

General guidelines

General Types

ALKYLATING agents

ANTI METABOLITES

ANTIBIOTICS

MITOTIC INHIBITORS

HORMONAL agents

IMMUNOSUPPRESANTS

Alkylating Agents

DYNAMICS: cause cell death or mutation

INDICATIONS: Palliative treatment of chronic lymphocytic leukemia, malignant lymphomas, Hodgkin’s disease, cancers of the breast, lungs and ovaries

ADVERSE EFFECTS: Bone marrow depression, anorexia, alopecia, N/V

Alkylating Agents

Busulfan

Carboplatin

Carmustine

Chlorambucil

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Cisplatin

Cyclophosphamide

Ifosphamide

Mecholethamine

Alkylating Agents

Nursing Interventions

Monitor CBC weekly

Hydrate patient well

Pre-medicate with anti-emetics

Monitor IV site

Prepare epi, steroids and antiH1

Drug Specific Side effects

ANTI-METABOLITE

DYNAMICS: interferes with the building block of DNA synthesis

INDICATIONS: Myelocytic leukemia, acute lymphocytic leukemia, cancers of breast, cervix, colon, liver, ovaries

ADVERSE EFFECTS: GI disturbance, oral and anal inflammation, bone marrow depression, alopecia, renal dysfunction and thrombocytopenia

General Guidelines for anti-metabolites

Monitor CBC and Platelets weekly

Evaluate renal functions

Take temperature Q 4 hours

Aseptic techniques

Bleeding, anemia, infection and nausea

Oral hygiene

Lots of fluids (2-3 liters/day)

Intake and output, nutrition

The protocols for handling- follow them

Emphasize protective isolation

Anti-metabolites

Capecitabine

Cytarabine

Fluouracil

Methotrexate

Mercaptopurine

Thioguanine

Floxuridine

Anti-Metabolites

Nursing Interventions

Evaluate complete blood count

Pre-medicate with anti-emetics

Safety measures for dizziness

Instruct to report fever, sore throat, rash and bleeding

Provide small, frequent feedings

Suncreens for photosensitivity

Anti-Metabolites

Nursing Interventions

When administering methotrexate, prepare to administer leucovorin (folinic acid or citrovorum factor) to prevent toxicity

Anti-Neoplastic Antibiotics

DYNAMICS: these kill cancer cells by disrupting the DNA synthesis and breaking up the DNA linkages

INDICATIONS: Leukemia, carcinomas, adenocarcinoma

ADVERSE EFFECTS: bone marrow suppression, alopecia, NAVD, renal toxcity

Anti-Neoplastic Antibiotics

Bleomycin

Dactinomycin

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Daunorubicin

Doxorubicin

Idarubicin

Mitocycin

Plicamycin

Anti-Neoplastic Antibiotics

Daunorubicinà CHF and Dysrhythmia

Doxorubicinà Cardiotoxicity

Bleomycinà pulmonary toxicity

Plicamycinà excessive bleeding

Anti-Neoplastic Antibiotics

NURSING INTERVENTIONS

Monitor blood tests, cardiac functions

Ensure that the patient is well-hydrated

Provide small, frequent feedings

Advise wig for alopecia

Instruct to maintain oral hygiene

Assess the ECG frequently

MITOTIC INHIBITORS

DYNAMICS: kill the cells as the process of Mitosis begins by blocking the mitotic spindles causing cell death

INDICATIONS: Combination therapy for reproductive cancer, cancers of the lungs, Lymphomas

ADVERSE EFFECTS: bone marrow suppression, NAVD, renal and hepatic toxicity , alopecia

MITOTIC INHIBITORS

Etoposide

Teniposide

Vinblastine

Vincristine (Oncovin)

Vinorelbine

MITOTIC INHIBITORS

Vincristine (Oncovin)

Can cause NEUROTOXICITY

Cause severe bone depressionà check CBC

MITOTIC INHIBITORS

NURSING INTERVENTIONS

Arrange for blood tests

Avoid direct skin and eye contact with drugs

Ensure hydration

Small, frequent meals

Wig

Anti-emetics

Hormone and Immunomodulators

DYNAMICS: receptor-site specific drugs that block the specific hormones in the cancer

INDICATIONS: Breast cancer, prostate cancer

ADVERSE EFFECTS: menopause associated effects like hot flashes, vaginal dryness. Bone marrow depression and HYPERCALCEMIA

Hormone and Immunomodulators

Tamoxifen à anti-estrogen

Anastrazole

Estramustine

Letrozole

Testolactone

Toremifene

Goserelinà GnRH analogue

Flutamide

Fluoxymesteroneà an ANDROGEN

Diethylstilbestrol (DES)à estrogen preparation

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Hormone and Immunomodulators

NURSING INTERVENTIONS

Arrange for blood tests to monitor bone marrow depression

Provide small, frequent meals

Advise comfort measures for menopausal symptoms

Utilize BARRIER methods of contraception

Miscellaneous

L-Asparaginase

Enzyme that destroys ASPARAGINE needed by malignant cells for protein synthesis

Indicated for acute lymphocytic leukemia

Adverse effects: PANCREATITIS, bone marrow depression, fatal hyperthermia, hypersensitivity

Miscellaneous

Azathioprine

Used as adjunct to cyclosporine and steroids to suppress immune system

CAN CAUSE bone marrow suppression and increase incidence of cancers

Taken with meals

Avoid crowds, maintain hygeine

Anti-emetics

Metoclopromide

Odansetron

Dronabinol

In Summary

Cancers arise from a single abnormal cell that multiplies and grows

Cancers can come from epithelia cells- CARCINOMA or mesenchymal cells- SARCOMA

Cancer cells lose their normal functions and they grow uninhibited

In Summary

Anti-neoplastic agents affects both the normal cells and the cancers cells

They act by disrupting cell function and division

Most cancer drugs are MOST effective against cancer cells that multiply RAPIDLY

In Summary

The ULTIMATE GOAL of cancer therapy is to decrease the size of the cancer so that the body’s immune system can eliminate the cancer

Anti-cancer drugs are BEST given in combination so as to affect the cancer cells in various stages

In Summary

ADVERSE effects commonly encountered with cancer therapy are related to damage to RAPIDLY multiplying cells like the BONE MARROW, hair follicle and Gastro-intestinal lining

In Summary

In general, these drugs SHOULD NOT be used during pregnancy or lactation because they may cause serious adverse effects on the FETUS

Hematologic Drugs

Hematologic drugs

There are numerous agents utilized to maintain, preserve and restore circulation. The three important dysfunction of blood are thrombosis, bleeding and anemia are commonly treated with various agents. The common ones that nurses must REVIEW are the:

Anticoagulants

Antilipemics

Antiplatelets (antithombotics)

Thrombolytics

Anti-anemics or Hematinics

Drugs to treat bleeding

The Anti-Coagulants

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The anticoagulants interfere with the coagulation process by interfering with the clotting cascade and thrombin formation. These agents are used to inhibit clot formation, but they do NOT dissolve existing clots.

The Anticoagulants commonly used are:

Heparin

Warfarin (Coumadin)

Dicumarol

Anisindione (Miradon)

Heparins

These are anticoagulants given orally or parenterally- SQ and IV.

Heparin is naturally found in the human liver that normally prevents clot formation.

Heparin is strongly acidic because of the presence of sulfate and carboxylic acid groups in the heparin chain.

Heparin

The mechanism of action of Heparin

Heparin (Liquamen Sodium) acts prophylactically to prevent the formation of blood clots in the vasculature.

It combines with ANTITHROMBIN III, a substance in our blood sometimes called heparin factor that inactivates THROMBIN.

By inhibiting the action of thrombin, conversion of fibrinogen to fibrin does not occur and the formation of a fibrin clot is prevented.

Heparins

Clinical Indications of Heparins

deep vein thrombosis

pulmonary embolism

coronary thrombosis,

patients with artificial heart valves and stroke patients

Heparins

Contraindications of heparin

Anticoagulants are not given to patients with bleeding disorders, peptic ulcers and patients who underwent recent eye/brain/spinal surgery.

It is NOT given to patients with severe liver and renal disease, hemophilia, and CVA.

Heparin is a large protein molecule that cannot pass through the placenta easily and can be given to pregnant women.

Heparins

Pharmacokinetics: the Adverse Effects of Heparin

INCREASES the clotting time and also DECREASES the platelet count. In this regard, monitoring of the aPTT/PTT (N= 20-30 seconds) and platelet count is required.

Hematologic effects: increased bleeding, thrombocytopenia

Skin-itching and burning

Hypersensitivity reactions like chills, fever, urticaria or anaphylaxis can occur since heparin is obtained from animal sources.

Life threatening adverse effect is Hemorrhage

Heparins

The Nursing process and Heparin

Assessment

Patient history

Physical examination- the nurse obtains baseline vital signs and physical assessment.

She must obtain laboratory results of the complete blood count, platelet count and activated partial thromboplastin time (aPTT), and clotting time.

Heparins

IMPLEMENTATION:

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Monitor the aPTT closely (it should be 1.5-2.5 times normal value)

Monitor vital signs and hematological status regularly.

Monitor signs of bleeding- hematuria, epistaxis, ecchymoses, Hypotension and occult blood in stool

Have available ANTIDOTE for heparin- PROTAMIME SULFATE

Heparins

IMPLEMENTATION:

Instruct the client not to use any over the counter drug without notifying the physician

Administer heparin subcutaneously in the abdominal region, using a 25-28-gauge needle at a 90-degree angle. DO NOT MASSAGE OR RUB THE AREA as this may cause bruising.

Advise patient not to smoke, use electric razors to shave, use soft toothbrush and control sudden hemorrhage by direct pressure for 5-10 minutes.

Provide gently skin and oral care.

Heparins

Evaluation

Monitor the effectiveness of the medication:

Decreased formation of clot

PTT is 2x the normal

The Oral Anticoagulants

There are three commonly used oral anticoagulant agents in the hospital

Warfarin- most commonly used, synthesized from dicumarol

Dicumarol

Anisindone

The Oral Anticoagulants

Pharmacodynamics: the mechanism of Action of the Oral agents

These agents INHIBIT the liver synthesis of the Vitamin K clotting factors – factors II, VII, IX, and X.

The Oral Anticoagulants

Clinical indications of oral anticoagulants

These drugs are used to prevent blood clotting in patients with thrombophlebitis

pulmonary embolism and embolism from atrial fibrillation.

Because Warfarin crosses the placental barrier, it is NOT given to pregnant mothers.

The Oral Anticoagulants

Contraindications and precautions

Oral anti-coagulants are NOT given to patients with bleeding disorders, peptic ulcers, severe renal/liver diseases, hemophilia, CVA blood dyscrasias and eclampsia.

It is NOT given to pregnant mothers because it is teratogenic and can cause abortion

The Oral Anticoagulants

Pharmacokinetics:

Oral anticoagulants prolong the clotting time and are monitored by the Prothrombine Time (PT- average of 9-12 seconds). This is usually performed before administering the next dose. The PT level should be 1.5-2 times the reference value to be therapeutic.

The normal INR is 1-2. If the patient is on oral anticoagulant therapy, the INR is maintained at an INR of 2.0-3.0. If the INR is below the recommended range, warfarin is increased. If it is above the recommended range, warfarin should be reduced.

The Oral Anticoagulants

Pharmacokinetics: the Adverse Effects of Warfarin

Hematologic effects: increased bleeding, thrombocytopenia

Anorexia, nausea, vomiting, diarrhea, abdominal cramps, rash and fever.

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Alopecia, bone marrow depression, and dermatitis.

Life threatening adverse effect is Hemorrhage

The Oral Anticoagulants

The Nursing process and Warfarin

Assessment

Patient history-. The nurse determines the current medications taken, PREGNANCY, and history of recent surgery.

Physical examination- the nurse obtains baseline vital signs and physical assessment.

laboratory results of the complete blood count, platelet count and Prothrombin time, INR and clotting time.

The Oral Anticoagulants

Implementation

Monitor vital signs and hematological status

Monitor signs of bleeding- hematuria, epistaxis, black tarry stools, echymoses, Hypotension and occult blood in stool

Have available ANTIDOTE for warfarin- VITAMIN K or phytonadione.

The Oral Anticoagulants

Implementation

Advise patient not to smoke, use electric razors to shave, use soft toothbrush and control sudden hemorrhage by direct pressure for 5-10 minutes. Provide gently skin and oral care.

Instruct the patient to avoid foods high in vitamin K like spinach, nuts

The Oral Anticoagulants

Evaluation

Monitor the effectiveness of the medication

Decreased formation of blood clots

Check the PT and INR

Should be 2x the normal

Anti-platelets

These are agents decrease the formation of the platelet plug by decreasing the responsiveness of the platelets to various stimuli that would cause them to stick and combine together on a vessel wall

Aspirin

Dipyridamole

Sulfinpyrazone

Ticlopidine

Clopidogrel

Glycoprotein receptor antagonists

Abciximab

Eptifibatide

Tirofiban

Anti-platelets

The mechanism of action of platelet inhibitors

These agents INHIBIT the aggregation of platelets in the clotting process by blocking receptor sites on the platelet membrane, preventing platelet-to-platelet interaction, thereby prolonging the bleeding time.

Anti-platelets

Clinical indications

Prevention of myocardial infarction and stroke

Prevention of a repeat myocardial infarction

Prevention of stroke for those with transient ischemic attack

In patients with graft to maintain its patency.

Anti-platelets

Pharmacodynamics: the adverse effects of Antiplatelets

Bleeding is the most common side effect

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GIT- gum bleeding, gastric bleeding, tarry stools

CNS- headache, dizziness and weakness

Skin- petechiae, bruising, allergy

ASPIRIN toxicity: tinnitus

Anti-platelets

Nursing considerations

Determine if the patient is allergic or sensitive to the medications

Monitor closely the vital signs and bleeding areas

Instruct the patient to take drug with food

Monitor the bleeding time, clotting time and platelet count

Anti-platelets

Nursing considerations

Suggest safety measures including the use of an electric razor and avoidance of contact sports.

Provide increased precautions against bleeding during invasive procedures.

Use pressure dressings and ice to decrease excessive blood loss.

Monitor for tinnitus

The Thrombolytics

These thrombolytic agents are used to activate the natural anticlotting fibrinolytic mechanism to convert plasminogen to plasmin, which destroys and breaks down the fibrin threads in the blood clot (FIBRINOLYSIS). The result is clot disintegration.

The commonly used thrombolytics “---ase”

Streptokinase

Urokinase

Tissue plasminogen activator (t-PA) or alteplase

Anistreplase

Reteplase

The Thrombolytics

The mechanisms of actions of each agent

Streptokinase and urokinase are ENZYMES that act SYSTEMICALLY to dissolve the blood clots by activating plasminogen to plasmin.

The Thrombolytics

Clinical indications of thrombolytics

Myocardial infarction

Pulmonary embolism

Thromboemboilic stroke

Peripheral arterial thrombosis and

to open clotted IV catheters.

The Thrombolytics

Pharmacokinetics: The adverse effects of Streptokinase

CVS- Hypotension and dysrhythmias (usually upon reperfusion of the heart)

Hematological: increased bleeding- the most common effect.

Headache, nausea, flush, rash and fever

Allergic reaction- especially steptokinase and urokinase

Major adverse effect- hemorrhage.

The Thrombolytics

Implementation.

Monitor signs of active bleeding from mouth and rectum bleeding- hematuria, epistaxis, echymoses

Have available ANTIDOTE for thrombolytics: AMINOCAPROIC ACID!

Have available blood for emergency use.

Advise patient not to smoke, use electric razors to shave, use soft toothbrush and control sudden hemorrhage by direct pressure for 5-10 minutes.

Provide gently skin and oral care. As much as possible, avoid frequent venipuncture.

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The Thrombolytics

Evaluation

Monitor the effectiveness of the medication

Clot lysis

The Agents to treat bleeding

Aminocaproic acid and tranexamic acid

These are fibrin stabilizers that maintain or stabilize the clot in the bleeding vessels

The Agents to treat bleeding

Protamine sulfate

This agent antagonizes the anticoagulant effects of heparin. It is derived from fish testis and is high in arginine content.

The positive charge interacts with the negative charge of heparin to forma stable inactive complex.

The Agents to treat bleeding

Vitamin K

Vitamin K is given to antagonize the effects of the oral anticoagulants.

The response to Vitamin K is slow, requiring about 24 hours

thus, if immediate hemostasis or bleeding control is required, fresh frozen plasma should be ordered by the physician.

Antihyperlipidemics

These drugs target the problem of elevated serum lipids

Resins and bile acid sequestrants

Cholestyramine

Colestipol

Fibric Acid Derivatives

Clofibrate

Gemfibrozil

Fenofibrate

HMG CoA reductase inhibitors= “statins”

Atorvastatin

Cerivastatin

Fluvastatin

Lovastatin

Pravastatin

Simvastatin

Nicotinic acid

Probucol

statins

Pharmacodynamics: The mechanism of action of the Statins

These agents INHIBIT the enzyme HMG CoA reductase in the synthesis of cholesterol.

By inhibiting the important enzyme in cholesterol production in the liver, the statins decrease the plasma concentration of cholesterol and lower the LDL level with slight increase in the HDL level.

statins

Therapeutic indications

These agents are given to patients with CORONAY ARTERY DISEASE and hyperlipidemia, hypercholesterolemia

These statins are very effective in all types of hyperlipidemias.

The antianemics: Iron preparations and Epoetin

Iron preparations

Iron is important for hemoglobin formation.

The iron preparations are:

Ferrous sulfate

Ferrous fumarate

Ferrous gluconate

The antianemics: Iron preparations and Epoetin

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Side-effects:

GIT- constipation (usually), diarrhea, vomiting, epigastric pain, gastric ulceration and darkening of stools.

Liquid preparation can stain the teeth, and injectable iron can cause tissue discoloration

Other- dizziness

The antianemics: Iron preparations and Epoetin

Drug-Drug interaction

Tetracyclines and penicillamine- combine with iron preparations and render the iron unabsorbable.

Antacids and cimetidine- decrease iron absorption and effects

Foods can impair iron absorption but they should be taken with iron to reduce GI discomfort.

Milk containing foods, coffee, tea and eggs are NOT given with iron because they delay iron absorption.

The antianemics: Iron preparations and Epoetin

Implementation

Encourage the patient to eat iron-rich foods like liver, lean meat, egg yolk, dried beans, green leafy vegetables.

Administer iron preparations orally with foods to decrease GI discomfort.

If increased absorption is necessary, administer IN BETWEEN meals with full glass of water or juice.

It is best to offer citrus juices because the vitamin C content can increase iron absorption.

Instruct the patient to swallow the whole tablet and remain upright for 30 minutes to prevent esophageal corrosion from reflux.

DO NOT administer iron together with or within 1 hour of ingesting tetracyclines, antacids, milk and milk-containing products.

Advise clients to increase fluid intake and consume fiber rich foods if constipation becomes a problem.

The antianemics: Iron preparations and Epoetin

Implementation

Warn the patient of possible iron poisoning if tablets are left within child’s reach. Emphasize that the therapeutic effect of iron therapy may not be apparent until several weeks.

If injecting a parenteral iron preparation, inject DEEP IM utilizing the Z-track method to avoid leakage into the subcutaneous tissues and skin.

Offer straw if giving liquid iron preparation to avoid staining the teeth.

To prevent undue alarm, instruct the patient that the stools may turn black or dark green. This is a harmless occurrence.

The antianemics: Iron preparations and Epoetin

Evaluation

The nurse evaluates the effectiveness of the drug therapy by determining that the client is not fatigued, with absence of pallor, and with hemoglobin results within desired range.

Erythropoietin

The mechanism of action of epoetin alfa

(Epogen)

This drug acts like the natural glycoprotein erythropoietin to stimulate the production of RBC in the bone marrow.

Erythropoietin

Clinical indications

It is given SUBCUTANEOUSLY or INTRAVENOUSLY for the treatment of anemia associated with renal failure or for patients on dialysis.

It is also used in patients for blood transfusion to decrease the need for blood in surgical patients.

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Erythropoietin

Pharmacodynamics: the adverse effects of epoetin alfa

CNS- headache, fatigue, asthenia, dizziness and seizures- these are due to the cellular response to the glycoprotein.

GIT- nausea, vomiting and diarrhea

CVS- hypertension, edema and chest pain due to increase RBC number

Erythropoietin

Implementation

Administer the drug SC or IV usually 3 times per week.

Monitor the IV access line if given IV. Do not mix with other solutions

Determine periodically the level of hematocrit and iron stores during therapy. If patient does not respond to the drug, reevaluate the cause of anemia.

Maintain seizure precaution on stand by as seizure can occur.

Provide comfort measures like small frequent feedings and pain medications for headache.

Provide thorough health teaching: need for lifetime injection

Erythropoietin

Evaluation

Monitor patient response to the drug= increased hemoglobin

Nursing Pharmacology

Dermatological Agents

Dermatological Agents

Agents which are applied and exert their effects where they are administered

Dermatological Agents

The target tissue for most agents is the SKIN

Topical therapy

Use of active drugs in an inactive vehicle like oil

Employs the use of topical preparations

Topical preparations

SOAKS

LOTIONS

SOLUTIONS

PASTE

CREAM

OINTMENT

POWDER

Commonly used topical agents

Caustics

Silver nitrate, Zinc chloride and Ferric subsulfate

Used for granulation tissues, epitheliomas and granulomas (benign skin tumors)

Applied directly over the lesions

Keratolytics

Lactic acid, Glycolic acids, Urea, Salicylic acids

Causes desquamation of skin and denaturation of skin proteins

Destroys the skin keratin

Applied over the skin lesions like acne, calluses, warts and tinea versicolor

Cytostatic agents

Anthralin, Tars, Liquid carbonic detergents

Suppresses the DNA synthesis of skin cells

Used for psoriasis, eczema, seborrheic dermatitis

Applied over the skin lesions

Cytotoxic agents

Cantharadin, Podophylin, Fluouracil

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Kill the cell by either binding to DNA microtubules, destroys mitochondria or inhibiting DNA synthesis

Used for warts (condyloma), basal cell carcinoma

Demelanizing agents - whitening

Hydroquinone- bleaching agent that inhibits TYROSINASE activity in the melanocytesà decreased melanin

Monobenzone- bleaching agent that is MORE potent than hydroquinone causing irreversible and permanent whitening à used in extensive vitiligo

Melanizing agents- darkening

Psoralens- promotes melanin production in the kin, used for psoriasis and mild vitiligo to darken the skin

Methoxalen- photosensitizer that makes the skin sensitive to UV rays, used for psoriasis

Anti-infectives

Antibacterial drugs like bacitracin, terramycin

Antifungal agents like clotrimazole, ketoconazole, nystatin, tolnaftate

Antiviral agents like zovirax

Scabicides and pediculocides

Gamma Benzene Hexachloride, Crotamiton, Benzoyl benzoate, Permethrin

Applied to body or hair to kill the parasites

Retinoids

Include natural compounds and synthetic derivatives of vitamin A

Effects on the skinà reduction of keratinization that leads to acne formation ; reduction of SEBUM production and removal of Propionebacterium acne

Retinoids

Tretinoin (Retin-A)- reduces acne formation

Applied topically at night before bedtime

Side-effects: skin peeling, erythema, burning and stinging sensation

Retinoids

Isotretinoin (ACCUTANE)

Normalizes the keratinization process of cell

Taken ORALLY

Adverse effect: TERATOGENIC

Pharmacology

Migrane/ Ophthalmic and ENT DRUGS

Migraine Drugs

The underlying cause of migraine is believed to be ARTERIAL DILATATION

May be due to release of bradykinin, serotonin and other chemicals

Migraine Drugs

The ERGOT derivatives are the most frequently used drug to treat migraine previuosly

Recently the TRIPTANs have been introduced

ERGOT derivatives

These agents cause CONSTRICTION of the blood vessels in the cranium and decrease the pulsation of the arteries

ERGOT derivatives

Dihydroergotamine

Ergotamine

Methysergide

ERGOT derivatives

Adverse effects

Numbness

Muscle pain

Chest pain

Arrhythmias

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ERGOTISM- nausea, vomiting, hypoperfusion, chest pain, confusion

ERGOT derivatives

NURSING RESPONSIBILITIES

Avoid prolonged use and over-use

Assess for presence of decubitus ulcer and gangrene

Give the medication BEFORE the pain occurs

Provide supportive measures

Teach about ergotism

The TRIPTANs

These agents BIND to serotonin receptors in the cranial blood vessels causing VASOCONSTRICTION

The TRIPTANs

Sumatriptan

Zolmitriptan

Naratriptan

Rizatriptan

The TRIPTANs

Can be given orally, nasally, and SC

The TRIPTANs

ADVERSE Effects

Numbness, tingling sensation,coldness

Dizziness

GI discomfort

Chest pain

The TRIPTANs

NURSING RESPONSIBILITIES

Administer the drugs before the pain worsens

Monitor blood pressure

Measures for safety

Give with food to decrease GI effects

Glaucoma

Increased intra-ocular pressure

Glaucoma

Two types

1. Open angle

2. Closed angle

Glaucoma

Glaucoma

MEDICAL MANAGEMENT

1. Laser surgery

2. Drug therapy to lower Increased IOP

MiOtics to cause cOnstriction

Adrenergics, beta-blockers and CAI to cause reduced production

Miotics

These are also called parasympathomimetic agents

Their action mimics the parasympathetic nervous system

The Cholinergic Agonists

DIRECTLY acts by occupying the receptor in the eyes

Pilocarpine

Direct acting cholinergic agonists

Pharmacodynamics

Similar to acetylcholine and directly act on the acetylcholine receptors

Pilocarpine

Parasympathetic stimulation will cause:

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DUMBELS

urination

miosis (pupil constriction)

Pilocarpine

Clinical use

1. Relief of increased intraocular pressure of glaucoma by inducing miosis

Pilocarpine

Direct acting cholinergic agonists: Adverse effects (DUMBELS)

CVS- bradycardia, heart block, hypotension

GIT- nausea, vomiting, diarrhea, increased salivation, lacrimation

GUT- sense of urgency, sphincter relaxation

Others- increased sweating, headache, miosis, photophobia, blurred vision

Pilocarpine

Nursing considerations

1. Assure proper administration of ophthalmic preparations

2. Provide safety precautions- because of poor visual acuity and blurred vision

3. Promote cool environment, maintain access to the bathroom (urination)

Other Drugs for Glacoma

CAI- acerazolamide

Adrenergic agent- epineprhine

The ANTI-cholinergics

Anticholinergics:

Prototype: Atropine

dicyclomine

glycopyrrolate

propantheline

scopolamine

The ANTI-cholinergics

Anticholinergics: pharmacodynamics

These agents work by BLOCKING or COMPETING with acetylcholine for the acetylcholine receptors

BEST taken BEFORE MEALS

Atropine

Depresses salivation

Decreases bronchial secretions

Mydriasis

Cyclopedia

Inhibits vagal response in the heart

Reverses cholinergic toxicity

Atropine

Scopolamine

Decreases nausea and vomiting associated with motion sickness

Anticholinergic

Contraindications of anticholinergic

1. Known allergy

2. Glaucoma

3. Bladder obstruction (like PBH)

Anticholinergic

Adverse effects: anticholinergic effects

CNS- blurred vision, pupil DILATION, photophobia, cycloplegia and increased Intraocular pressure

GI- dry mouth, constipation, bloatedness

CVS- tachycardia, palpitations

GU- urinary retention

Others- decreased sweating, flushing

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Anticholinergic

Nursing considerations

Provide comfort measures

Frequent mouth care

Provide increased fluids

Protect eyes fro lights

Advise to avoid hazardous activities

Provide high-fiber diet and laxative

Avoid extremes of temperature

Instruct to void before administering the drug

Anticholinergic

Nursing considerations

2. Monitor for toxicity:

3. Ensure adequate hydration to prevent hyperpyrexia

The ANTIHISTAMINES

Also called H1 blockers or H1 antagonists, these are agents designed to relieve respiratory symptoms and to treat allergic conditions.

The ANTIHISTAMINES

The anti-histamines are group according to the “generation”.

The FIRST GENERATION agents have greater anticholinergic effects and can cause more sedation and drowsiness! These agents cause drowsiness.

The SECOND GENERATION agents have fewer anticholinergic effects that is why they cause less sedation.

The ANTIHISTAMINES

The FIRST GENERATION ANTIHISTAMINES

1. Azatadine 11. Dimenhydrinate

2. Azelastine 12. Diphenhydramine

3. Brompheniramine 13. Hydroxyzine

4. Buclizine 14. Meclizine

5. Cetirizine 15. Methdilazine

6. Chlorpheniramine 16. Promethazine

7. Clemastine 17. Tripelenamine

8. Cyclizine 18. Carbinoxamine

9. Cyproheptadine 19. Trimeprazine

10. Dexchlorpheniramine20 Triprolidine

The ANTIHISTAMINES

The SECOND GENERATION ANTIHISTAMINES

Fexofenadine

Loratidine

Azelastine

Cetirizine

Anti-Histamine

These agents SELECTIVELY block the effects of histamine at the HISTAMINE-1 receptor sites in the target tissue by competing with histamine for receptor, decreasing the cellular responses

They also have anticholinergic and antipruritic properties.

Anti-Histamine

Clinical Indications for Use in respiratory system

1. rhinitis

2. allergic sinusitis

3. uncomplicated urticaria and angioedema.

4. Motion sickness

Anti-Histamine

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1. CNS- drowsiness and sedation, most pronounced if first generation agents are used

2. Fatigue, dizziness and disturbed coordination.

3. Anticholinergic effects= drying of the respiratory mucus membrane, GI upset and nausea, arrhythmias, dysuria, urinary retention

4. Skin dryness

Anti-Histamine

Implementation

The nurse should administer the drug on an EMPTY stomach, or 1 hour before or 2 hours after meals to increase the absorption.

Give with food if GI upset occurs

Anti-Histamine

Implementation

Offer sugarless lozenges or hard candy to counteract dryness of the mouth. Give frequent oral care

Provide safety measures if drowsiness may occur. Side rails up, assist in ambulation, and advise not to drive or operate dangerous machineries or delicate tasks.

Anti-Histamine

Nursing implementation

Increase humidity in the room by utilizing nebulizers and provide adequate hydration

Allow the patient to void first before administering the drug.

Anti-Histamine

Evaluation

Monitor patient’s response to the drug, the adverse effects and the effectiveness of comfort measures employed

Decreased allergic symptoms

Decreased occurrence of rhinitis

The Topical Nasal Decongestants

These include:

Ephedrine

Oxymetazoline

Phenylephrine

Tetrahydrozoline

Xylometazoline

The Topical Nasal Decongestants

Pharmacodynamics: action

These agents imitate the effects of the sympathetic nervous system to cause vasoconstriction, leading to decreased edema and decreased inflammation of the nasal membranes.

The Topical Nasal Decongestants

Pharmacokinetics: administration and preparations

These agents are available as nasal sprays or drops used to relieve the discomfort of nasal congestion

Topical Decongestants

Clinical use of the agents

symptoms of nasal congestion in colds, rhinitis, and sinusitis.

These can be used when dilation of the nares is desired to facilitate medical examination and to relieve the pain and congestion of otitis media.

Topical Decongestants

Contraindication and precautions

erosions of the nasal mucosa.

These following conditions need precautions- narrow angle glaucoma, hypertension, diabetes, thyroid diseases, and CAD because these conditions may be aggravated by the sympathetic activity.

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Topical Decongestants

Pharmacodynamics: the drug effects

Local effects- local stinging and burning, erosions and ulceration if used for prolonged time.

If used for more than 5 to 10 days, rebound congestion can occur, also called rhinitis medicamentosa. The reflex reaction to vasoconstriction is a rebound vasodilatation as the drug effect wears off.

Sympathomimetic effects= tachycardia, hypertension, urinary retention.

Topical Decongestants

Nursing Responsibilities

Teach the patient the proper administration of the drug to ensure therapeutic effect.

The patients must clear the nasal passages first before use; tilt the head back when applying and keep tilted for a few seconds after administration

Emphasize that the drugs should NOT be used for more than 5 to 10 days and to seek medical attention if symptoms persist.

Topical Decongestants

Provide safety measures if dizziness or sedation occur to prevent injury

Institute other measures to help relieve discomfort of congestion like humidity, increased fluid intake, cool environment and avoidance of smoking

Anesthetics

Pharmacology in Nursing

Anesthetics

Anesthetics are drugs that are used to cause complete or partial loss of sensation.

The numerous anesthetics can be broadly classified as :

General

Local anesthetics

Anesthetics

General anesthetics

are central nervous system depressants used to produce loss of pain sensation and consciousness.

Anesthetics

Local anesthetics

are drugs used to cause loss of pain sensation and feeling in a designated area of the body without the systemic effects associated with severe CNS depression

General Anesthetics

Produce the following effects:

analgesia (loss of pain sensation),

unconsciousness and

amnesia

General Anesthetics

Blockage of autonomic reflexes prevents response of involuntary reflexes to injury to the body that might compromise a patient’s cardiac, respiratory, gastrointestinal and immune status.

Blockage of muscle reflexes prevents jerking movements that might interfere with the success of the surgical procedure.

Stages of Anesthesia Depth

Usually trained individuals with the special equipments ready for life support administer the agents

The patient undergoes through a predictable stages known as STAGES of ANESTHESIA: 1 to 4

Stages of Anesthesia

STAGE 1

Referred to as the Analgesia Stage is loss of pain sensation

with the patient still conscious and able to communicate

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Stages of Anesthesia

STAGE 2- the Excitement Stage,

A period of excitement and often combative behaviors are present such as restlessness, with signs of sympathetic stimulation (tachycardia, increased respiration and blood pressure changes)

Stages of Anesthesia

STAGE 3

Surgical Anesthesia stage, involves relaxation of skeletal muscles, return of regular respiration, and progressive loss of eye reflexes and pupil dilatation.

This is the best stage for surgical procedure.

Stages of Anesthesia

STAGE 4

Medullary Paralysis stage is a very deep CNS depression with loss of respiratory and vasomotor center stimuli in which death can occur rapidly.

General Anesthesia

INHALATIONAL (gas and volatile liquid)

Halothane

Enflurane

Nitrous oxide

INTRAVENOUS

Barbiturates (Thiopenthal and Methohexital)

Ketamine

Profofol

General Anesthetics

Action of General Anesthetics

The mechanism is not clear. It is known that depression of the reticular activating system and the cerebral cortex occurs.

Therapeutic use of General Anesthetics

Sedation and anesthesia for surgical procedures

General Anesthetics

The anesthetics are administered by trained personnel

Maintain equipment on standby to provide airway and mechanical ventilation in cases of severe drug reaction

Monitor temperature regularly, monitor pulse, BP and respiration

Carefully monitor patient in the recovery room until he regains consciousness and able to communicate

Provide safety and comfort measures.

Pre-operative teaching must be provided and information about the anesthetics should be incorporated in the teaching plan.

Local Anesthesia

Local anesthetics are drugs that cause a loss of sensation in limited areas of the body to abolish pain.

They are powerful nerve blockers injected locally.

Systemic absorption of the anesthetics can produce numerous side effects.

Local Anesthesia

Administering Local Anesthetics

There are five types of local anesthetic administration- topical, infiltration, field block, nerve block, and IV regional anesthesia.

Topical Administration- anesthetic agents are incorporated in vehicles such as creams, ointments, gels, lotions, drops and sprays.

Infiltration- this involves injecting the anesthetic directly into the tissues to be treated.

Local Anesthesia

Field block – involves injecting the anesthetic agents al around the area that will be affected by the surgical operation.

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Nerve Block- involves injecting the anesthetic agents at some point along the nerve that runs to and from the region of operation. One example is epidural anesthesia.

Intravenous regional Anesthesia involves carefully draining all of the blood from an arm or leg, securing a tourniquet to prevent the aesthetic from entering the

Local Anesthesia

Examples of Local anesthetics: The “CAINES”

Lidocaine

Dibucaine

Procaine

Tetracaine

Local Anesthesia

Local anesthetics work by causing a temporary interruption in the production and conduction of nerve impulses.

They affect the permeability of sodium (preventing it from entering the cell) and chloride (by entering the cell).

The nerve cells become more negative, with resultant decrease in depolarizationà no transmission of pain

Local Anesthesia

These agents are used for infiltration anesthesia, peripheral nerve block, spinal anesthesia and relief of local pain.

Local Anesthesia

The side effects of local anesthetics

Local effects- local irritation and skin breakdown

CNS effects if systemic absorption occurs- headache, restlessness, anxiety, dizziness, tremors and blurred vision.

GI system- nausea, vomiting

Cardio- arrhythmias, peripheral vasodilation, myocardial depression, and rarely, cardiac arrest

Local Anesthesia

Nursing Responsibilities

Maintain emergency equipment on standby to provide life-support in cases of severe reactions

Ensure that drugs are available for managing hypotension, cardiac arrest and CNS alterations.

Provide adequate hydration to patients receiving spinal anesthesia. Position the client supine for up to 12 hours after spinal anesthesia to minimize spinal headache

Local Anesthesia

Nursing Responsibilities

Provide safety and comfort measures such as side-rails up, frequent skin care and supportive care

Give health teaching to explain things the patient needs to know to allay fears.

Muscle Relaxants

Pharmacology in Nursing

Overview

Skeletal muscle relaxants are drugs that decrease muscle tone and movements by reducing skeletal muscle activities

Types of Relaxants

Central acting: Baclofen, Chlorphenesin, Chlorzoxazone

Peripheral Acting: “Curium” and “curare”

Direct acting: Dantrolene

Central Acting Relaxants

These agents DEPRESS the CNS or BLOCK the transmission of nerve impulses from the spinal cord to the skeletal muscles

The result is muscle relaxation

Peripheral Acting Relaxants

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These agents interfere with nerve transmission between the motor end plate and the skeletal muscle receptors

These agents block the DEPOLARIZATON and REPOLARIZATION activity of the skeletal muscles leading to PARALYSIS

BACLOFEN (Lioresal)

Pharmacodynamics: inhibits the synaptic reflexes at the SPINAL cord

The action does not reduce consciousness

This is prescribed for the treatment of spasticity and muscle sprain; also as adjunct to physical therapy

BACLOFEN (Lioresal)

Kinetics: absorbed orally, excreted in the feces and kidney.

Thus drug is very lipophilic that can pass the brain barrierà drowsiness

BACLOFEN (Lioresal)

Side-effects:

CNS: Drowsiness, dizziness and confusion

CVS: Hypotension, bradycardia

GU: Urinary frequency and impotence

BACLOFEN (Lioresal)

Nursing Responsibilities:

Avoid the use together with alcohol

Perform a baseline mental status examination

Supervise any ambulation and transfers to ensure safety

Monitor blood pressure

Check deep tendon reflexes for any symptom of toxicity

BACLOFEN (Lioresal)

Evaluate for effectiveness of the drug

The client displays evidence of increased range of motion exercise

Decreased spasticity

Dantrolene

Pharmacodynamics: this agent acts DIRECTLY on skeletal muscle to interfere with CALCIUM release from the sarcoplasmic reticulum

This is useful in conditions like: MALIGNANT hyperthermia and spastic conditions like multiple sclerosis, spinal cord injury and CVA

Dantrolene

Kinetics: absorbed orally, can be given IV, excreted in kidney

Dantrolene

Side-effects:

CNS: muscle weakness, drowsiness and dizziness

CVS: tachycardia an phlebitis

GIT: HEPATITIS

GU; Urinary frequency, hematuria and retention

Dantrolene

Nursing Responsibility

Note that this drug is not used if patient has liver dysfunction as hepatitis can occur

Peripheral Acting Relaxants

Usually group into: NON-DEPOLARIZING and DEPOLARIZING agents

NON-DEPOLARIZING are COMPETITIVE agents that BLOCK acetylcholine receptors

DEPOLARIZING agent excites the muscle initially then prevents the muscle from contracting

Peripheral Acting Relaxants

Non DEPOLARIZING Agents:

Atracurium besylate

Pancuronium

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Rocuromium

Vecuronium

Tubocurarine

DEPOLARIZING

Succinylcholine

Peripheral Acting Relaxants

General indications:

Adjunct to general anesthesia

Muscle relaxation during surgery, mechanical ventilation and orthopedic manipulation

Peripheral Acting Relaxants

Side effects

Respiratory depression

Muscle weakness

Cardiac arrhythmias

Hypotension

Peripheral Acting Relaxants

Nursing Responsibilities

Note that paralysis occurs from head to toe and recovery starts from toe to head

Monitor the BP and respiratory status frequently

Note that consciousness in NOT affected

Peripheral Acting Relaxants

Evaluate for drug usefulness

The client will maintain skeletal relaxation without respiratory depression

Peripheral Acting Relaxants

Succinylcholine

A depolarizing agent that prolongs the depolarization of the muscle end plate

Used as muscle relaxant during surgery, intubation and short procedures

Administered IV, relaxation occurs in 1 minute and lasts for 6 minutes

COMPUTATIONS

Oral Medications: Solids

Quantity of Drug =

Desired dose/Stock dose

(D/S = Q)

Oral/Parenteral: Liquids

Quantity of Drug =

Desired dose

--------------------- X Dilution

Stock dose x

(D/S x dilution = Q)

IV Fluid Flow Rate

gtts/min

Vol. in cc x gtt factor

----------------------------

no. of hours x 60 mins.

IV Fluid Flow Rate

cc/hr

Vol. in cc

-------------------------

no. of hours

IV Fluid Flow Rate

Duration in hours

Vol. in cc

-------------------------

cc/hr

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Conversion of Temp

oC to oF

(oC x 1.8) + 32

oF to oC

(oF – 32) (.55)

THANK YOU.

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