antihistamines,decongestants,antitussives,andexpectorants drugs affecting the respiratory system

Antihistamines,Antihistamines,

Decongestants,Decongestants,

Antitussives,Antitussives,

andand

ExpectorantsExpectorants

Drugs Affecting theDrugs Affecting theRespiratory Respiratory

SystemSystem

Understanding the Understanding the Common ColdCommon Cold Most caused by viral infection Most caused by viral infection

(rhinovirus or influenza virus—the (rhinovirus or influenza virus—the “flu”)“flu”)

Understanding the Understanding the Common ColdCommon Cold Virus invades tissues (mucosa) of upper Virus invades tissues (mucosa) of upper

respiratory tract, causing upper respiratory tract, causing upper respiratory infection (URI).respiratory infection (URI).

Excessive mucus production results from Excessive mucus production results from the inflammatory response to this the inflammatory response to this invasion.invasion.

Fluid drips down the pharynx into the Fluid drips down the pharynx into the esophagus and lower respiratory tract, esophagus and lower respiratory tract, causing cold symptoms: sore throat, causing cold symptoms: sore throat, coughing, upset stomach.coughing, upset stomach.

Understanding the Understanding the Common ColdCommon Cold Irritation of nasal mucosa often Irritation of nasal mucosa often

triggers the sneeze reflex.triggers the sneeze reflex. Mucosal irritation also causes Mucosal irritation also causes

release of several inflammatory release of several inflammatory and vasoactive substances, and vasoactive substances, dilating small blood vessels in the dilating small blood vessels in the nasal sinuses and causing nasal nasal sinuses and causing nasal congestion.congestion.

Treatment of the Treatment of the Common ColdCommon Cold Involves combined use of Involves combined use of

antihistamines, nasal antihistamines, nasal decongestants, antitussives, and decongestants, antitussives, and expectorants.expectorants.

Treatment is SYMPTOMATIC only, Treatment is SYMPTOMATIC only, not curative.not curative.

Symptomatic treatment does not Symptomatic treatment does not eliminate the causative pathogen.eliminate the causative pathogen.

Upper Respiratory TractUpper Respiratory Tract

Upper and Lower Respiratory Upper and Lower Respiratory TractsTracts

Treatment of the Treatment of the Common ColdCommon Cold Difficult to identify whether cause Difficult to identify whether cause

is viral or bacterial.is viral or bacterial. Treatment is “empiric therapy,” Treatment is “empiric therapy,”

treating the most likely cause.treating the most likely cause. Antivirals and antibiotics may be Antivirals and antibiotics may be

used, but viral or bacterial cause used, but viral or bacterial cause may not be easily identified.may not be easily identified.

AntihistaminesAntihistamines

Drugs that directly compete with Drugs that directly compete with histamine histamine for specific receptor for specific receptor sites.sites.

Two histamine receptors:Two histamine receptors:– HH11 histamine-1 histamine-1

– HH22 histamine-2 histamine-2


HH22 Blockers or H Blockers or H22 Antagonists Antagonists– Used to reduce gastric acid in PUDUsed to reduce gastric acid in PUD– Examples: Examples: cimetidine (Tagamet), cimetidine (Tagamet),

ranitidine ranitidine (Zantac), or (Zantac), or famotidine famotidine (Pepcid)(Pepcid)


HH11 antagonists are commonly antagonists are commonly referred referred to asantihistaminesto asantihistamines

Antihistamines have several effectsAntihistamines have several effects::– AntihistaminicAntihistaminic– AnticholinergicAnticholinergic– SedativeSedative

Antihistamines: Antihistamines: Mechanism of ActionMechanism of ActionBLOCK action of histamine at the BLOCK action of histamine at the

receptor sitesreceptor sites Compete with histamine for binding at Compete with histamine for binding at

unoccupied receptors.unoccupied receptors. CANNOT push histamine off the CANNOT push histamine off the

receptor if already bound.receptor if already bound.

Antihistamines: Antihistamines: Mechanism of ActionMechanism of Action

The binding of HThe binding of H11 blockers to the blockers to the histamine receptors prevents the histamine receptors prevents the adverse consequences of adverse consequences of histamine stimulation:histamine stimulation:– VasodilationVasodilation– Increased gastrointestinal and Increased gastrointestinal and

respiratory secretionsrespiratory secretions– Increased capillary permeabilityIncreased capillary permeability

Antihistamines: Antihistamines: Mechanism of ActionMechanism of Action

More effective in preventing the More effective in preventing the actions of histamine rather than actions of histamine rather than reversing themreversing them

Should be given early in Should be given early in treatment, before treatment, before all the histamine binds to the all the histamine binds to the receptorsreceptors

Histamine vs. Histamine vs. Antihistamine EffectsAntihistamine Effects

Cardiovascular (small blood vessels)Cardiovascular (small blood vessels) Histamine effects:Histamine effects:

– Dilation and increased permeability Dilation and increased permeability (allowing substances to leak into (allowing substances to leak into tissues)tissues)

Antihistamine effects:Antihistamine effects:– Prevent dilation of blood vessels Prevent dilation of blood vessels – Prevent increased permeabilityPrevent increased permeability


Smooth Muscle (on exocrine glands)Smooth Muscle (on exocrine glands) Histamine effects:Histamine effects:

– Stimulate salivary, gastric, lacrimal, Stimulate salivary, gastric, lacrimal, and and bronchial secretionsbronchial secretions

Antihistamine effects:Antihistamine effects:– Prevent salivary, gastric, lacrimal, Prevent salivary, gastric, lacrimal,

and and bronchial secretionsbronchial secretions


Immune System Immune System

(Release of substances commonly (Release of substances commonly associated with allergic reactions)associated with allergic reactions)

Histamine effects:Histamine effects:– Mast cells release histamine and other Mast cells release histamine and other

substances, resulting in allergic reactions.substances, resulting in allergic reactions. Antihistamine effect:Antihistamine effect:

– Binds to histamine receptors, thus Binds to histamine receptors, thus preventing histamine from causing a preventing histamine from causing a response.response.

Antihistamines: Other Antihistamines: Other EffectsEffects

Skin:Skin: Block capillary permeability, wheal-Block capillary permeability, wheal-

and-flare formation, itchingand-flare formation, itching

Anticholinergic:Anticholinergic: Drying effect that reduces nasal, Drying effect that reduces nasal,

salivary, and lacrimal gland secretions salivary, and lacrimal gland secretions (runny nose, tearing, and itching eyes)(runny nose, tearing, and itching eyes)

Sedative:Sedative: Some antihistamines cause drowsinessSome antihistamines cause drowsiness

Antihistamines: Antihistamines: Therapeutic UsesTherapeutic Uses

Management of:Management of:

Nasal allergiesNasal allergies

Seasonal or perennial allergic rhinitis Seasonal or perennial allergic rhinitis (hay fever)(hay fever)

Allergic reactionsAllergic reactions

Motion sicknessMotion sickness

Sleep disordersSleep disorders

AntihistaminesAntihistamines10 to 20% of general population is 10 to 20% of general population is

sensitive sensitive to various to various environmental allergies.environmental allergies.

Histamine-mediated disorders:Histamine-mediated disorders:– Allergic rhinitis Allergic rhinitis

(hay fever, mold and dust allergies)(hay fever, mold and dust allergies)

– AnaphylaxisAnaphylaxis

– Angioneurotic edemaAngioneurotic edema

– Drug feversDrug fevers

– Insect bite reactionsInsect bite reactions

– Urticaria (itching)Urticaria (itching)

Antihistamines: Antihistamines: Therapeutic UsesTherapeutic Uses

Also used to relieve symptoms Also used to relieve symptoms associated associated with the common with the common cold:cold:

Sneezing, runny noseSneezing, runny nose Palliative treatment, not curativePalliative treatment, not curative

Antihistamines: Side Antihistamines: Side effectseffects

Anticholinergic (drying) effects, Anticholinergic (drying) effects, most common:most common:– Dry mouthDry mouth– Difficulty urinatingDifficulty urinating– ConstipationConstipation– Changes in visionChanges in vision

DrowsinessDrowsiness– (Mild drowsiness to deep sleep)(Mild drowsiness to deep sleep)

Antihistamines: Two Antihistamines: Two TypesTypes

Traditional Traditional

or or Nonsedating/Peripherally ActingNonsedating/Peripherally Acting

Antihistamines:Antihistamines:

TraditionalTraditional OlderOlder Work both peripherally and centrallyWork both peripherally and centrally Have anticholinergic effects, making Have anticholinergic effects, making

them more effective than nonsedating them more effective than nonsedating agents in some casesagents in some cases

Examples:Examples: diphenhydramine (Benadryl)diphenhydramine (Benadryl)chlorpheniramine (Chlor-chlorpheniramine (Chlor-

Trimeton)Trimeton)

Antihistamines:Antihistamines:

Nonsedating/Peripherally ActingNonsedating/Peripherally Acting Developed to eliminate unwanted side Developed to eliminate unwanted side

effects, mainly sedationeffects, mainly sedation Work peripherally to block the actions of Work peripherally to block the actions of

histamine; thus, fewer CNS side effectshistamine; thus, fewer CNS side effects Longer duration of action (increases Longer duration of action (increases

compliance)compliance)

Examples:Examples: fexofenadine (Allegra)fexofenadine (Allegra)loratadine (Claritin)loratadine (Claritin)

Nursing Implications: Nursing Implications: AntihistaminesAntihistamines

Gather data about the condition or Gather data about the condition or allergic reaction that required treatment; allergic reaction that required treatment; also, assess for drug allergies.also, assess for drug allergies.

Contraindicated in the presence of acute Contraindicated in the presence of acute asthma attacks and lower respiratory asthma attacks and lower respiratory diseases.diseases.

Use with caution in increased intraocular Use with caution in increased intraocular pressure, cardiac or renal disease, pressure, cardiac or renal disease, hypertension, asthma, COPD, peptic ulcer hypertension, asthma, COPD, peptic ulcer disease, BPH, or pregnancy.disease, BPH, or pregnancy.


Instruct patients to report excessive Instruct patients to report excessive sedation, confusion, or hypotension.sedation, confusion, or hypotension.

Avoid driving or operating heavy Avoid driving or operating heavy machinery, and do not consume machinery, and do not consume alcohol or other CNS depressants.alcohol or other CNS depressants.

Do not take these medications with Do not take these medications with other prescribed or OTC medications other prescribed or OTC medications without checking with prescriber.without checking with prescriber.


Best tolerated when taken with mealsBest tolerated when taken with meals—reduces GI upset.—reduces GI upset.

If dry mouth occurs, teach patient to If dry mouth occurs, teach patient to perform frequent mouth care, chew perform frequent mouth care, chew gum, or suck on hard candy gum, or suck on hard candy (preferably sugarless) to ease (preferably sugarless) to ease discomfort.discomfort.

Monitor for intended therapeutic Monitor for intended therapeutic effects.effects.

DecongestantsDecongestants

Nasal CongestionNasal Congestion

Excessive nasal secretionsExcessive nasal secretions Inflamed and swollen nasal Inflamed and swollen nasal

mucosamucosa

Primary causes:Primary causes:– AllergiesAllergies– Upper respiratory infections Upper respiratory infections

(common cold)(common cold)


Two main types are used:Two main types are used: Adrenergics (largest group)Adrenergics (largest group) CorticosteroidsCorticosteroids


Two dosage forms:Two dosage forms: OralOral Inhaled/topically applied to the nasal Inhaled/topically applied to the nasal

membranesmembranes

Oral DecongestantsOral Decongestants

Prolonged decongestant effects, Prolonged decongestant effects, but delayed onsetbut delayed onset

Effect less potent than topical Effect less potent than topical No rebound congestionNo rebound congestion Exclusively adrenergicsExclusively adrenergics Examples:Examples: phenylephrine phenylephrine

pseudoephedrine pseudoephedrine (Sudafed)(Sudafed)

Topical Nasal Topical Nasal DecongestantsDecongestants

Both adrenergics and steroidsBoth adrenergics and steroids Prompt onsetPrompt onset PotentPotent Sustained use over several days Sustained use over several days

causes rebound congestion, causes rebound congestion, making the condition worsemaking the condition worse

Topical Nasal Topical Nasal DecongestantsDecongestants

Adrenergics:Adrenergics:ephedrine (Vicks)ephedrine (Vicks) naphazoline naphazoline (Privine)(Privine)

oxymetazoline (Afrin)oxymetazoline (Afrin) phenylephrine phenylephrine (Neo Synephrine)(Neo Synephrine)

Intranasal Steroids:Intranasal Steroids:beclomethasone dipropionate beclomethasone dipropionate (Beconase, Vancenase)(Beconase, Vancenase)

flunisolide (Nasalide)flunisolide (Nasalide)

Nasal Decongestants: Nasal Decongestants: Mechanism of ActionMechanism of Action

Site of action: blood vessels Site of action: blood vessels surrounding surrounding nasal sinusesnasal sinuses

AdrenergicsAdrenergics– Constrict small blood vessels that supply Constrict small blood vessels that supply

URI structuresURI structures– As a result, these tissues shrink and nasal As a result, these tissues shrink and nasal

secretions in the swollen mucous secretions in the swollen mucous membranes membranes are better able to drainare better able to drain

– Nasal stuffiness is relievedNasal stuffiness is relieved

Nasal Decongestants: Nasal Decongestants: Mechanism of ActionMechanism of Action

Site of action: blood vessels Site of action: blood vessels surrounding surrounding nasal sinusesnasal sinuses

Nasal steroidsNasal steroids– Anti-inflammatory effectAnti-inflammatory effect– Work to turn off the immune system cells Work to turn off the immune system cells

involved in the inflammatory involved in the inflammatory responseresponse

– Decreased inflammation results in Decreased inflammation results in decreased congestiondecreased congestion

– Nasal stuffiness is relievedNasal stuffiness is relieved

Nasal Decongestants: Nasal Decongestants: Drug EffectsDrug Effects

Shrink engorged nasal mucous Shrink engorged nasal mucous membranesmembranes

Relieve nasal stuffinessRelieve nasal stuffiness

Nasal Decongestants: Nasal Decongestants: Therapeutic UsesTherapeutic Uses

Relief of nasal congestion associated with:Relief of nasal congestion associated with: Acute or chronic rhinitisAcute or chronic rhinitis Common coldCommon cold SinusitisSinusitis Hay feverHay fever Other allergiesOther allergies

May also be used to reduce swelling of the nasal May also be used to reduce swelling of the nasal passage and facilitate visualization of the passage and facilitate visualization of the nasal/pharyngeal membranes before surgery or nasal/pharyngeal membranes before surgery or diagnostic procedures.diagnostic procedures.

Nasal Decongestants: Nasal Decongestants: Side EffectsSide Effects

AdrenergicsAdrenergics SteroidsSteroidsnervousnessnervousness local mucosal local mucosal

dryness dryness and irritationand irritation

insomniainsomnia

palpitationspalpitations

tremorstremors

(systemic effects due to adrenergic (systemic effects due to adrenergic stimulation of stimulation of the heart, blood the heart, blood vessels, and CNS)vessels, and CNS)

Nursing Implications: Nursing Implications: Nasal Nasal

DecongestantsDecongestants Decongestants may cause Decongestants may cause

hypertension, palpitations, and hypertension, palpitations, and CNS stimulation—avoid in patients CNS stimulation—avoid in patients with these conditions.with these conditions.

Assess for drug allergies.Assess for drug allergies.

Nursing Implications: Nursing Implications: DecongestantsDecongestants

Patients should avoid caffeine and Patients should avoid caffeine and caffeine-containing products.caffeine-containing products.

Report a fever, cough, or other Report a fever, cough, or other symptoms lasting longer than a symptoms lasting longer than a week.week.

Monitor for intended therapeutic Monitor for intended therapeutic effects.effects.

AntitussivesAntitussives

Cough PhysiologyCough Physiology

Respiratory secretions and foreign Respiratory secretions and foreign objects are naturally removed by objects are naturally removed by the the

cough reflexcough reflex– Induces coughing and expectorationInduces coughing and expectoration– Initiated by irritation of sensory Initiated by irritation of sensory

receptors in the respiratory tractreceptors in the respiratory tract

Two Basic Types of Two Basic Types of Cough Cough

Productive CoughProductive Cough– Congested, removes excessive Congested, removes excessive

secretionssecretions Nonproductive CoughNonproductive Cough

– Dry coughDry cough

CoughingCoughing

Most of the time, coughing is Most of the time, coughing is beneficialbeneficial

Removes excessive secretionsRemoves excessive secretions Removes potentially harmful foreign Removes potentially harmful foreign

substancessubstances

In some situations, coughing can be In some situations, coughing can be harmful, such as after hernia harmful, such as after hernia repair surgeryrepair surgery

AntitussivesAntitussives

Drugs used to stop or reduce Drugs used to stop or reduce coughingcoughing

Opioid and nonopioid Opioid and nonopioid (narcotic and non-narcotic)(narcotic and non-narcotic)

Used only for NONPRODUCTIVE Used only for NONPRODUCTIVE coughs!coughs!

Antitussives: Antitussives: Mechanism of ActionMechanism of Action

OpioidOpioid Suppress the cough reflex by direct Suppress the cough reflex by direct

action on the cough center in the action on the cough center in the medulla.medulla.

Examples:Examples: codeine (Robitussin A-C, codeine (Robitussin A-C, Dimetane-DC) Dimetane-DC)

hydrocodonehydrocodone

Antitussives: Antitussives: Mechanism of ActionMechanism of Action

NonopioidNonopioid Suppress the cough reflex by numbing Suppress the cough reflex by numbing

the stretch receptors in the respiratory the stretch receptors in the respiratory tract and preventing the cough reflex tract and preventing the cough reflex from being stimulated.from being stimulated.

Examples:Examples: benzonatate (Tessalon)benzonatate (Tessalon)dextromethorphan (Vicks dextromethorphan (Vicks

Formula 44,Formula 44,Robitussin-DM)Robitussin-DM)

Antitussives: Antitussives: Therapeutic UsesTherapeutic Uses

Used to stop the cough reflex Used to stop the cough reflex when the cough is nonproductive when the cough is nonproductive and/or harmfuland/or harmful

Antitussives: Side Antitussives: Side EffectsEffects

BenzonatateBenzonatate Dizziness, headache, sedationDizziness, headache, sedation

DextromethorphanDextromethorphan Dizziness, drowsiness, nauseaDizziness, drowsiness, nausea

OpioidsOpioids Sedation, nausea, vomiting, lightheadedness, Sedation, nausea, vomiting, lightheadedness,

constipationconstipation

Nursing Implications: Nursing Implications: Antitussive AgentsAntitussive Agents

Perform respiratory and cough Perform respiratory and cough assessment, and assess for allergies.assessment, and assess for allergies.

Instruct patients to avoid driving or Instruct patients to avoid driving or operating heavy equipment due to operating heavy equipment due to possible sedation, drowsiness, or possible sedation, drowsiness, or dizziness.dizziness.

If taking chewable tablets or lozenges, If taking chewable tablets or lozenges, do not drink liquids for 30 to 35 do not drink liquids for 30 to 35 minutes afterward.minutes afterward.

Nursing Implications: Nursing Implications: Antitussive AgentsAntitussive Agents

Report any of the following symptoms Report any of the following symptoms to the caregiver:to the caregiver:– Cough that lasts more than a weekCough that lasts more than a week– A persistent headacheA persistent headache– Fever Fever – RashRash

Antitussive agents are for Antitussive agents are for NONPRODUCTIVE coughs.NONPRODUCTIVE coughs.

Monitor for intended therapeutic effects.Monitor for intended therapeutic effects.


Drugs that aid in the Drugs that aid in the expectoration expectoration (removal) of mucus(removal) of mucus

Reduce the viscosity of secretionsReduce the viscosity of secretions Disintegrate and thin secretionsDisintegrate and thin secretions

Expectorants: Expectorants: Mechanisms of ActionMechanisms of Action

Direct stimulation Direct stimulation

oror Reflex stimulationReflex stimulation

Final result: thinner mucus that is easier Final result: thinner mucus that is easier to removeto remove

Expectorants: Expectorants: Mechanism of ActionMechanism of Action

Direct stimulation:Direct stimulation: The secretory glands are stimulated The secretory glands are stimulated

directly to increase their production of directly to increase their production of respiratory tract fluids.respiratory tract fluids.

Examples: terpin hydrate, iodine-Examples: terpin hydrate, iodine-containing containing products such products such as iodinated glycerol and as iodinated glycerol and potassium iodide (direct and indirect potassium iodide (direct and indirect

stimulation)stimulation)

Expectorants: Expectorants: Mechanism of ActionMechanism of Action

Reflex stimulation:Reflex stimulation: Agent causes irritation of the GI tract.Agent causes irritation of the GI tract. Loosening and thinning of respiratory Loosening and thinning of respiratory

tract secretions occur in response to tract secretions occur in response to this irritation.this irritation.

Examples: guaifenesin, syrup of ipecacExamples: guaifenesin, syrup of ipecac

Expectorants: Drug Expectorants: Drug EffectsEffects

By loosening and thinning sputum By loosening and thinning sputum and bronchial secretions, the and bronchial secretions, the tendency to cough is indirectly tendency to cough is indirectly diminished.diminished.

Expectorants: Expectorants: Therapeutic UsesTherapeutic Uses

Used for the relief of nonproductive Used for the relief of nonproductive coughs associated with:coughs associated with:Common coldCommon cold PertussisPertussis

BronchitisBronchitis InfluenzaInfluenza

LaryngitisLaryngitis MeaslesMeasles

PharyngitisPharyngitis

Coughs caused by chronic paranasal Coughs caused by chronic paranasal sinusitissinusitis

Expectorants: Common Expectorants: Common Side EffectsSide Effects

guaifenesinguaifenesin terpin hydrateterpin hydrate

Nausea, vomitingNausea, vomiting Gastric upsetGastric upset

Gastric irritationGastric irritation (Elixir has high (Elixir has high alcohol alcohol content)content)

Nursing Implications: Nursing Implications: ExpectorantsExpectorants

Expectorants should be used with Expectorants should be used with caution in the elderly, or those with caution in the elderly, or those with asthma or respiratory insufficiency.asthma or respiratory insufficiency.

Patients taking expectorants should Patients taking expectorants should receive more fluids, if permitted, to help receive more fluids, if permitted, to help loosen and liquefy secretions.loosen and liquefy secretions.

Report a fever, cough, or other Report a fever, cough, or other symptoms lasting longer than a week.symptoms lasting longer than a week.

Monitor for intended therapeutic effects.Monitor for intended therapeutic effects.

Bronchodilators Bronchodilators and Other and Other

Respiratory Respiratory AgentsAgents

Asthmatic ResponseAsthmatic Response

Bronchodilators: Bronchodilators: Xanthine DerivativesXanthine Derivatives Plant alkaloids: caffeine, theobromine, Plant alkaloids: caffeine, theobromine,

and theophyllineand theophylline Only theophylline is used as a Only theophylline is used as a

bronchodilatorbronchodilator

Examples:Examples: aminophyllineaminophyllinedyphilline dyphilline oxtriphyllineoxtriphyllinetheophylline (Bronkodyl, Slo-theophylline (Bronkodyl, Slo-

bid,bid,Theo-Dur,Uniphyl)Theo-Dur,Uniphyl)

Drugs Affecting Drugs Affecting the Respiratory the Respiratory SystemSystem BronchodilatorsBronchodilators

– Xanthine derivativesXanthine derivatives– Beta-agonistsBeta-agonists

AnticholinergicsAnticholinergics Antileukotriene agentsAntileukotriene agents CorticosteroidsCorticosteroids Mast cell stabilizersMast cell stabilizers

Exchange of Oxygen and Carbon Exchange of Oxygen and Carbon DioxideDioxide

Bronchodilators: Bronchodilators: Xanthine Derivatives Xanthine Derivatives Mechanism of ActionMechanism of Action

Increase levels of energy-producing cAMP*Increase levels of energy-producing cAMP* This is done competitively inhibiting This is done competitively inhibiting

phosphodiesterase (PDE), the enzyme that phosphodiesterase (PDE), the enzyme that breaks down cAMPbreaks down cAMP

Result: decreased cAMP levels, smooth Result: decreased cAMP levels, smooth muscle relaxation, bronchodilation, and muscle relaxation, bronchodilation, and increased airflowincreased airflow

*cAMP = cyclic adenosine monophosphate*cAMP = cyclic adenosine monophosphate

Bronchodilators: Bronchodilators: Xanthine Derivatives Xanthine Derivatives Drug EffectsDrug Effects

Cause bronchodilation by relaxing smooth Cause bronchodilation by relaxing smooth muscles of the airways.muscles of the airways.

Result: relief of bronchospasm and greater Result: relief of bronchospasm and greater airflow into and out of the lungs.airflow into and out of the lungs.

Also causes CNS stimulation.Also causes CNS stimulation. Also causes cardiovascular stimulation: Also causes cardiovascular stimulation:

increased force of contraction and increased increased force of contraction and increased HR, resulting in increased cardiac output and HR, resulting in increased cardiac output and increased blood flow to the kidneys (diuretic increased blood flow to the kidneys (diuretic effect).effect).

Bronchodilators: Bronchodilators: Xanthine Derivatives Xanthine Derivatives Therapeutic UsesTherapeutic Uses

Dilation of airways in asthmas, chronic Dilation of airways in asthmas, chronic bronchitis, and emphysemabronchitis, and emphysema

Mild to moderate cases of asthmaMild to moderate cases of asthma Adjunct agent in the management of Adjunct agent in the management of

COPDCOPD Adjunct therapy for the relief of Adjunct therapy for the relief of

pulmonary edema and paroxysmal pulmonary edema and paroxysmal nocturnal edema in left-sided heart failurenocturnal edema in left-sided heart failure

Bronchodilators: Bronchodilators: Xanthine Derivatives Xanthine Derivatives Side EffectsSide Effects

Nausea, vomiting, anorexiaNausea, vomiting, anorexia Gastroesophageal reflux during Gastroesophageal reflux during

sleepsleep Sinus tachycardia, extrasystole, Sinus tachycardia, extrasystole,

palpitations, ventricular palpitations, ventricular dysrhythmiasdysrhythmias

Transient increased urinationTransient increased urination

Bronchodilators: Beta-Bronchodilators: Beta-AgonistsAgonists Large group, sympathomimeticsLarge group, sympathomimetics Used during acute phase of Used during acute phase of

asthmatic attacksasthmatic attacks Quickly reduce airway constriction Quickly reduce airway constriction

and restore normal airflowand restore normal airflow Stimulate betaStimulate beta22 adrenergic adrenergic

receptors throughout the lungsreceptors throughout the lungs

Bronchodilators: Beta-Bronchodilators: Beta-Agonists Three typesAgonists Three types

Nonselective adrenergicsNonselective adrenergics– Stimulate alphaStimulate alpha11, beta, beta11 (cardiac), and beta (cardiac), and beta22

(respiratory) receptors.(respiratory) receptors.Example: epinephrineExample: epinephrine

Nonselective beta-adrenergicsNonselective beta-adrenergics– Stimulate both betaStimulate both beta11 and beta and beta22 receptors. receptors.

Example: isoproterenol (Isuprel)Example: isoproterenol (Isuprel) Selective betaSelective beta22 drugs drugs

– Stimulate only betaStimulate only beta22 receptors. receptors.Example: albuterolExample: albuterol

Bronchodilators: Beta-Bronchodilators: Beta-Agonists Mechanism of Agonists Mechanism of ActionAction Begins at the specific receptor Begins at the specific receptor

stimulatedstimulated Ends with the dilation of the airwaysEnds with the dilation of the airways

Activation of betaActivation of beta22 receptors activate receptors activate cAMP, which relaxes smooth muscles of cAMP, which relaxes smooth muscles of the airway and results the airway and results in bronchial dilation and increased in bronchial dilation and increased airflow.airflow.

Bronchodilators: Beta-Bronchodilators: Beta-Agonists Therapeutic Agonists Therapeutic UsesUses Relief of bronchospasm, bronchial asthma, Relief of bronchospasm, bronchial asthma,

bronchitis, and other pulmonary disease.bronchitis, and other pulmonary disease. Useful in treatment of acute attacks as Useful in treatment of acute attacks as

well well as prevention.as prevention.

Used in hypotension and shock.Used in hypotension and shock. Used to produce uterine relaxation to Used to produce uterine relaxation to

prevent premature labor.prevent premature labor. Hyperkalemia—stimulates potassium to Hyperkalemia—stimulates potassium to

shift into the cell.shift into the cell.

Bronchodilators: Beta-Bronchodilators: Beta-Agonists Agonists Side EffectsSide Effects

Alpha-Beta Alpha-Beta BetaBeta11 and Beta and Beta22BetaBeta22

(epinephrine)(epinephrine) (isoproterenol)(isoproterenol) (albuterol)(albuterol)

insomniainsomnia cardiac stimulationcardiac stimulationhypotensionhypotensionrestlessnessrestlessness tremortremor vascularvascular

headacheheadacheanorexiaanorexia anginal painanginal pain tremortremorcardiac stimulationcardiac stimulation vascular vascular headacheheadache tremortremorvascular headachevascular headache

Devices Used in Devices Used in Asthma TherapyAsthma Therapy Metered Dose Inhaler (MDI)Metered Dose Inhaler (MDI)

– Contains medication and Contains medication and compressed aircompressed air

– Delivers a specific amount of Delivers a specific amount of medication with each puffmedication with each puff

Devices Used in Devices Used in Asthma TherapyAsthma Therapy Metered Dose Inhaler (MDI)Metered Dose Inhaler (MDI)

– Contains medication and compressed Contains medication and compressed airair

– Delivers a specific amount of Delivers a specific amount of medication with each puffmedication with each puff

SpacerSpacer– Used with MDIs to help get Used with MDIs to help get

medication into the lungs instead of medication into the lungs instead of depositing on the back of the throatdepositing on the back of the throat

Devices Used in Devices Used in Asthma TherapyAsthma Therapy Dry powder inhalersDry powder inhalers

– Starting to replace MDIsStarting to replace MDIs– The patient turns the dial and a The patient turns the dial and a

capsule full of powder is puncturedcapsule full of powder is punctured– The patient then inhales the powderThe patient then inhales the powder

Devices Used in Devices Used in Asthma TherapyAsthma Therapy

Uses a stream of air Uses a stream of air that flows through that flows through liquid medication to liquid medication to make a fine mist to make a fine mist to be inhaledbe inhaled

Very effectiveVery effective Must be cleaned Must be cleaned

and taken care of and taken care of to reduce risk of to reduce risk of contaminationcontamination

Nebulizer

Respiratory Agents: Respiratory Agents: General Nursing General Nursing ImplicationsImplications Encourage patients to take measures Encourage patients to take measures

that promote a generally good state of that promote a generally good state of health in order to prevent, relieve, or health in order to prevent, relieve, or decrease symptoms of COPD.decrease symptoms of COPD.– Avoid exposure to conditions that precipitate Avoid exposure to conditions that precipitate

bronchospasms (allergens, smoking, stress, air bronchospasms (allergens, smoking, stress, air pollutants)pollutants)

– Adequate fluid intakeAdequate fluid intake– Compliance with medical treatmentCompliance with medical treatment– Avoid excessive fatigue, heat, extremes in Avoid excessive fatigue, heat, extremes in

temperature, caffeinetemperature, caffeine

Respiratory Agents: Respiratory Agents: General Nursing General Nursing ImplicationsImplications Encourage patients to get prompt Encourage patients to get prompt

treatment for flu or other treatment for flu or other illnesses, and to get vaccinated illnesses, and to get vaccinated against pneumonia or flu.against pneumonia or flu.

Encourage patients to always Encourage patients to always check with their physician before check with their physician before taking any other medication, taking any other medication, including OTC.including OTC.

Respiratory Agents: Respiratory Agents: General Nursing General Nursing ImplicationsImplications Perform a thorough assessment before Perform a thorough assessment before

beginning therapy, including:beginning therapy, including:– Skin colorSkin color– Baseline vital signsBaseline vital signs– Respirations (should be <12 or >24 Respirations (should be <12 or >24

breaths/min)breaths/min)– Respiratory assessment, including PORespiratory assessment, including PO22

– Sputum productionSputum production– AllergiesAllergies– History of respiratory problemsHistory of respiratory problems– Other medications Other medications

Respiratory Agents: Respiratory Agents: General Nursing General Nursing ImplicationsImplications Teach patients to take Teach patients to take

bronchodilators exactly as bronchodilators exactly as prescribed.prescribed.

Ensure that patients know how to Ensure that patients know how to use inhalers, MDIs, and have the use inhalers, MDIs, and have the patients demonstrate use of patients demonstrate use of devices.devices.

Monitor for side effects.Monitor for side effects.

Respiratory Agents: Respiratory Agents: Nursing ImplicationsNursing Implications Monitor for therapeutic effectsMonitor for therapeutic effects

– Decreased dyspneaDecreased dyspnea– Decreased wheezing, restlessness, and Decreased wheezing, restlessness, and

anxietyanxiety– Improved respiratory patterns with Improved respiratory patterns with

return to normal rate and qualityreturn to normal rate and quality– Improved activity toleranceImproved activity tolerance

Decreased symptoms and increased Decreased symptoms and increased ease of breathingease of breathing

Bronchodilators: Bronchodilators: Nursing Implications Nursing Implications Xanthine DerivativesXanthine Derivatives

Contraindications: history of PUD Contraindications: history of PUD or or GI disordersGI disorders

Cautious use: cardiac diseaseCautious use: cardiac disease Timed-release preparations Timed-release preparations

should not be crushed or chewed should not be crushed or chewed (causes gastric irritation)(causes gastric irritation)


Report to physician:Report to physician:

PalpitationsPalpitations NauseaNausea VomitingVomiting

WeaknessWeakness DizzinessDizziness Chest Chest painpain

ConvulsionsConvulsions


Be aware of drug interactions Be aware of drug interactions with:with: cimetidine, oral cimetidine, oral contraceptives, allopurinolcontraceptives, allopurinol

Large amounts of caffeine can Large amounts of caffeine can have deleterious effects.have deleterious effects.

Bronchodilators: Bronchodilators: Nursing Implications Nursing Implications Beta-Agonist Beta-Agonist DerivativesDerivatives

Albuterol, if used too frequently, loses Albuterol, if used too frequently, loses its betaits beta22-specific actions at larger -specific actions at larger doses.doses.

As a result, betaAs a result, beta11 receptors are receptors are stimulated, causing nausea, increased stimulated, causing nausea, increased anxiety, palpitations, tremors, and anxiety, palpitations, tremors, and increased increased heart rate.heart rate.

Bronchodilators: Bronchodilators: Nursing ImplicationsNursing ImplicationsBeta-Agonist Beta-Agonist DerivativesDerivatives

Patients should take medications Patients should take medications exactly exactly as prescribed, with no omissions or as prescribed, with no omissions or double doses.double doses.

Patients should report insomnia, Patients should report insomnia, jitteriness, restlessness, palpitations, jitteriness, restlessness, palpitations, chest pain, or chest pain, or any change in symptoms.any change in symptoms.

Anticholinergics: Anticholinergics: Mechanism of ActionMechanism of Action Acetylcholine (ACh) causes Acetylcholine (ACh) causes

bronchial constriction and bronchial constriction and narrowing of the airways.narrowing of the airways.

Anticholinergics bind to the ACh Anticholinergics bind to the ACh receptors, preventing ACh from receptors, preventing ACh from binding.binding.

Result: bronchoconstriction is Result: bronchoconstriction is prevented, airways dilate.prevented, airways dilate.

AnticholinergicsAnticholinergics

Ipratropium bromide (Atrovent) is the Ipratropium bromide (Atrovent) is the only anticholinergic used for only anticholinergic used for respiratory disease.respiratory disease.

Slow and prolonged actionSlow and prolonged action

Used to Used to preventprevent bronchoconstriction bronchoconstriction

NOT used for acute asthma NOT used for acute asthma exacerbations!exacerbations!

Anticholinergics: Side Anticholinergics: Side EffectsEffects

Dry mouth or throatDry mouth or throat Gastrointestinal Gastrointestinal distressdistress

HeadacheHeadache CoughingCoughing

AnxietyAnxiety

No known drug interactionsNo known drug interactions

AntileukotrienesAntileukotrienes

Also called leukotriene receptor Also called leukotriene receptor antagonists (LRTAs)antagonists (LRTAs)

New class of asthma medicationsNew class of asthma medications Three subcategories of agentsThree subcategories of agents

AntileukotrienesAntileukotrienes

Currently available agents:Currently available agents: montelukast (Singulair)montelukast (Singulair) zafirlukast (Accolate)zafirlukast (Accolate) zileuton (Zyflo)zileuton (Zyflo)

Antileukotrienes: Antileukotrienes: Mechanism of ActionMechanism of Action Leukotrienes are substances released Leukotrienes are substances released

when a trigger, such as cat hair or when a trigger, such as cat hair or dust, starts a series of chemical dust, starts a series of chemical reactions in the body.reactions in the body.

Leukotrienes cause inflammation, Leukotrienes cause inflammation, bronchoconstriction, and mucus bronchoconstriction, and mucus production.production.

Result: coughing, wheezing, shortnessResult: coughing, wheezing, shortnessof breathof breath

Antileukotrienes: Antileukotrienes: Mechanism of ActionMechanism of Action Antileukotriene agents Antileukotriene agents preventprevent

leukotrienes from attaching to leukotrienes from attaching to receptors on cells in the lungs receptors on cells in the lungs and in circulation.and in circulation.

Inflammation in the lungs is Inflammation in the lungs is blockedblocked, and asthma symptoms , and asthma symptoms are relieved.are relieved.

Antileukotrienes: Antileukotrienes: Drug EffectsDrug Effects

By blocking leukotrienes:By blocking leukotrienes: Prevent smooth muscle contraction of Prevent smooth muscle contraction of

the the bronchial airwaysbronchial airways

Decrease mucus secretionDecrease mucus secretion Prevent vascular permeabilityPrevent vascular permeability Decrease neutrophil and leukocyte Decrease neutrophil and leukocyte

infiltration infiltration to the lungs, preventing inflammationto the lungs, preventing inflammation

Antileukotrienes: Antileukotrienes: Therapeutic UsesTherapeutic Uses Prophylaxis and chronic Prophylaxis and chronic

treatment of asthma in adults and treatment of asthma in adults and children over age 12children over age 12

NOT meant for management of NOT meant for management of acute asthmatic attacksacute asthmatic attacks

Montelukast is approved for use Montelukast is approved for use in children age 2 and olderin children age 2 and older

Antileukotrienes: Side Antileukotrienes: Side EffectsEffectszileutonzileuton zafirlukastzafirlukastHeadacheHeadache HeadacheHeadache

DyspepsiaDyspepsia NauseaNausea

NauseaNausea DiarrheaDiarrhea

DizzinessDizziness Liver dysfunctionLiver dysfunction

InsomniaInsomnia

Liver dysfunctionLiver dysfunction

montelukast has fewer side effects montelukast has fewer side effects

Antileukotrienes: Antileukotrienes: Nursing ImplicationsNursing Implications Ensure that the drug is being used for Ensure that the drug is being used for

chronic management of asthma, not chronic management of asthma, not acute asthma.acute asthma.

Teach the patient the purpose of the Teach the patient the purpose of the therapy.therapy.

Improvement should be seen in about Improvement should be seen in about

1 week.1 week.

Antileukotrienes: Antileukotrienes: Nursing ImplicationsNursing Implications Check with physician before taking any Check with physician before taking any

OTC or prescribed medications—many OTC or prescribed medications—many drug interactions.drug interactions.

Assess liver function before beginning Assess liver function before beginning therapy.therapy.

Medications should be taken every night Medications should be taken every night on a continuous schedule, even if on a continuous schedule, even if symptoms improve.symptoms improve.

CorticosteroidsCorticosteroids

Anti-inflammatoryAnti-inflammatory Used for CHRONIC asthmaUsed for CHRONIC asthma Do not relieve symptoms of acute Do not relieve symptoms of acute

asthmatic attacksasthmatic attacks Oral or inhaled formsOral or inhaled forms Inhaled forms reduce systemic Inhaled forms reduce systemic

effectseffects May take several weeks before full May take several weeks before full

effects are seeneffects are seen

Corticosteroids: Corticosteroids: Mechanism of ActionMechanism of Action Stabilize membranes of cells that Stabilize membranes of cells that

release harmful bronchoconstricting release harmful bronchoconstricting substances.substances.

These cells are leukocytes, or white These cells are leukocytes, or white blood cells.blood cells.

Also increase responsiveness of Also increase responsiveness of bronchial smooth muscle to beta-bronchial smooth muscle to beta-adrenergic stimulation.adrenergic stimulation.

Inhaled CorticosteroidsInhaled Corticosteroids

beclomethasone dipropionate beclomethasone dipropionate (Beclovent, Vanceril)(Beclovent, Vanceril)

triamcinolone acetonide triamcinolone acetonide (Azmacort)(Azmacort)

dexamethasone sodium phosphate dexamethasone sodium phosphate (Decadron Phosphate Respihaler)(Decadron Phosphate Respihaler)

flunisolide (AeroBid)flunisolide (AeroBid)

Inhaled Inhaled Corticosteroids: Corticosteroids: Therapeutic UsesTherapeutic Uses Treatment of bronchospastic Treatment of bronchospastic

disorders disorders that are not controlled by that are not controlled by conventional bronchodilators.conventional bronchodilators.

NOT considered first-line agents NOT considered first-line agents for management of acute for management of acute asthmatic attacks asthmatic attacks or status asthmaticus.or status asthmaticus.

Inhaled Inhaled Corticosteroids: Corticosteroids: Side EffectsSide Effects Pharyngeal irritationPharyngeal irritation CoughingCoughing Dry mouthDry mouth Oral fungal infectionsOral fungal infections

Systemic effects are rare because of Systemic effects are rare because of the low the low doses used for inhalation therapy.doses used for inhalation therapy.

Inhaled Inhaled Corticosteroids: Corticosteroids: Nursing ImplicationsNursing Implications Contraindicated in patients with Contraindicated in patients with

psychosis, fungal infections, AIDS, TB.psychosis, fungal infections, AIDS, TB. Cautious use in patients with diabetes, Cautious use in patients with diabetes,

glaucoma, osteoporosis, PUD, renal glaucoma, osteoporosis, PUD, renal disease, CHF, edema.disease, CHF, edema.

Teach patients to gargle and rinse the Teach patients to gargle and rinse the mouth with water afterward to mouth with water afterward to prevent the development of oral prevent the development of oral fungal infections.fungal infections.

Inhaled Inhaled Corticosteroids: Corticosteroids: Nursing ImplicationsNursing Implications Abruptly discontinuing these Abruptly discontinuing these

medications can lead to serious medications can lead to serious problems.problems.

If discontinuing, should be weaned for If discontinuing, should be weaned for a period of 1 to 2 weeks, and only if a period of 1 to 2 weeks, and only if recommended by physician.recommended by physician.

REPORT any weight gain of more than REPORT any weight gain of more than 5 pounds a week or the occurrence of 5 pounds a week or the occurrence of chest pain.chest pain.

Mast Cell StabilizersMast Cell Stabilizers

cromolyn (Nasalcrom, Intal)cromolyn (Nasalcrom, Intal) nedocromil (Tilade)nedocromil (Tilade)

Mast Cell StabilizersMast Cell Stabilizers

Indirect-acting agents that prevent the Indirect-acting agents that prevent the release of the various substances that release of the various substances that cause bronchospasmcause bronchospasm

Stabilize the cell membranes of Stabilize the cell membranes of inflammatory cells (mast cells, inflammatory cells (mast cells, monocytes, macrophages), thus monocytes, macrophages), thus preventing release of harmful cellular preventing release of harmful cellular contentscontents

No direct bronchodilator activityNo direct bronchodilator activity Used prophylacticallyUsed prophylactically

Cellular Makeup of an Cellular Makeup of an Alveolus and Capillary SupplyAlveolus and Capillary Supply

Mast Cell Stabilizers: Mast Cell Stabilizers: Therapeutic UsesTherapeutic Uses Adjuncts to the overall management Adjuncts to the overall management

of COPDof COPD Used solely for prophylaxis, NOT for Used solely for prophylaxis, NOT for

acute asthma attacksacute asthma attacks Used to prevent exercise-induced Used to prevent exercise-induced

bronchospasmbronchospasm Used to prevent bronchospasm Used to prevent bronchospasm

associated with exposure to known associated with exposure to known precipitating factors, such as cold, dry precipitating factors, such as cold, dry air or allergensair or allergens

Mast Cell Stabilizers: Mast Cell Stabilizers: Side EffectsSide Effects

CoughingCoughing Taste changesTaste changes

Sore throatSore throat DizzinessDizziness

RhinitisRhinitis HeadacheHeadache

BronchospasmBronchospasm

Mast Cell Stabilizers: Mast Cell Stabilizers: Nursing ImplicationsNursing Implications For prophylactic use onlyFor prophylactic use only Contraindicated for acute exacerbationsContraindicated for acute exacerbations Not recommended for children under Not recommended for children under

age 5age 5 Therapeutic effects may not be seen for Therapeutic effects may not be seen for

up to 4 weeksup to 4 weeks Teach patients to gargle and rinse the Teach patients to gargle and rinse the

mouth with water afterward to minimize mouth with water afterward to minimize irritation to the throat and oral mucosairritation to the throat and oral mucosa

antihistamines,decongestants,antitussives,andexpectorants drugs affecting the respiratory system

Documents