antibiotic use in dentistry

8/6/2019 Antibiotic Use in Dentistry

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Antibiotic Use In DentistryAntibiotic Use In Dentistry


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Writing PrescriptionsWriting PrescriptionsRx: Drug Name (can be generic) Unit DoseRx: Drug Name (can be generic) Unit Dose

(ex: Pen V(ex: Pen V--K 500 mg, Elixer, Soln)K 500 mg, Elixer, Soln)

Disp: # of pills, milliliters (ml)Disp: # of pills, milliliters (ml)

Sig: Directions for use. q24h (daily), q12h, q8h, q6h, q4h,Sig: Directions for use. q24h (daily), q12h, q8h, q6h, q4h,

prn pain, till goneprn pain, till gone

Refills__Refills__ SignatureSignature

DEA #DEA #


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General RulesGeneral Rules

Write Legibly!!Write Legibly!!

Remember your audience (Generally nonRemember your audience (Generally non--docs)docs)

this will improve compliance.this will improve compliance. Preferable to order specific hourly dosage timePreferable to order specific hourly dosage time

(q12h vs. bid, q8h vs. tid, etc.)(q12h vs. bid, q8h vs. tid, etc.)

Sig: Specify # of pills to take each doseSig: Specify # of pills to take each dose Prescribe an endpoint. (prn pain, till gone)Prescribe an endpoint. (prn pain, till gone)


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Barry Brainfart Dental Clinic 666 Bite Me Ln

Crossbyte Falls, MN Ph: 555-YOU-HURTPt. Name: Address: DOB:

Rx: Date:

Di :

Si :

Refill Barry Brainfart, DDS

DEA:______________________


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Antibiotic StrategiesAntibiotic Strategies

Cardinal Rules: 1) Use the right drug.Cardinal Rules: 1) Use the right drug.

2) Use the right dose. 3) Use the correct2) Use the right dose. 3) Use the correct

dosing schedule. 4) Correct duration.dosing schedule. 4) Correct duration. Hard and FastHard and FastEspecially early. Why?Especially early. Why?

Use a loading dose to rapidly achieveUse a loading dose to rapidly achieve

therapeutic blood levels.therapeutic blood levels. Avoid combinations of bacteriostatic andAvoid combinations of bacteriostatic and

bacteriocidal drugs.bacteriocidal drugs.


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ConsiderationsConsiderations

Gram Positive?Gram Positive?

Gram Negative?Gram Negative?

Mixed Infection?Mixed Infection?

Anaerobes?Anaerobes?


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Discussion: Antibiotic ChoiceDiscussion: Antibiotic Choice

Narrow Spectrum?Narrow Spectrum? Extended/Broad Spectrum?Extended/Broad Spectrum?

Designer Antibiotics?Designer Antibiotics?

Anaerobes? Consider if the infection isAnaerobes? Consider if the infection ispresent > 3days or if no improvement.present > 3days or if no improvement.


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Narrow Spectrum AntibioticsNarrow Spectrum Antibiotics

Specific for the pathogen.Specific for the pathogen.

Fewer disturbances of nonFewer disturbances of non--pathogenicpathogenic

bacteria.bacteria. Fewer side effects.Fewer side effects.

Rapid response for sensitive organisms.Rapid response for sensitive organisms.

Ex: Pen VK, Pen G, ErythromycinEx: Pen VK, Pen G, Erythromycin


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Broad Spectrum AntibioticsBroad Spectrum Antibiotics

Affects both Gram + and GramAffects both Gram + and Gram bacteria,bacteria,

better for mixed infections.better for mixed infections.

May give up some effectiveness for Gram +May give up some effectiveness for Gram +to gain effectiveness for Gramto gain effectiveness for Gram --..

Examples: Amoxicillin, AmpicillinExamples: Amoxicillin, Ampicillin


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Common PathogensNecrotic pulp and apical abscesses

Obligate anaerobic bacteriaGram negative rods

Prevotella & porphyomonas spp.Fusobacterium spp.

Campylobacter rectus

Gram positive rodsEubacterium spp.

Actinomycetes spp.

Gram positive cocciPeptostreptococcus spp.

Facultative anaerobic bacteriaGram positive cocci

Strep and Entercoccus spp.


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Common PathogensCommon Pathogens

Periodontal DiseasesPeriodontal DiseasesGingivitisGingivitis

Fuso, strep, & actinomycetesFuso, strep, & actinomycetesAdult peritonitisAdult peritonitis

Bacteroides, porphyomonas,Bacteroides, porphyomonas,peptostreptococcus & prevotellapeptostreptococcus & prevotella

Acute necrotizing ulcerative gingivitisAcute necrotizing ulcerative gingivitisSpirochetes, prevotella, fusoSpirochetes, prevotella, fuso

Localized juvenile periodontitisLocalized juvenile periodontitisActinobacillusActinobacillus


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Common PathogensCommon Pathogens

Fungal InfectionsFungal InfectionsCandida spp.Candida spp.

Mucorales spp.Mucorales spp.


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Lets Talk About Resistance

Three main types Chromosome mediated

Spontaneous mutations

Non-major form of drug resistance

Rarely lead to complete resistance

Plasmid mediated (conjugation) VERY important from clinical standpoint

Mostly gram negs

Mediate resistance to multiple drugs

High transfer rate from cell to cell Transposon (transduction and transformation)

Phage mediated

Clinically important for Gram +


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Antibiotic ChoicesAntibiotic Choices


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-Lactams

Natural penicillins

Pen VK and Pen G MOA: Inhibit cell wall synthesis

Dose: 250-500 mg qid x 7-10 days

Contraindications: Allergies

Poor renal fxn

Adverse events: GI upset Drug interactions: oral contraceptives

Pregnancy category B


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-Lactams

Natural penicillins

Pen VK and Pen G

BactericidalAllergic reaction: rare (4 per 100,000)

Spectrum:

Strep, staph, enterococcus, neiseria, treponema, listeria

Resistance: Mostly staph (>80%)


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-Lactams

Amino-penicillins

Amoxicillin, ampicillin MOA: Inhibit cell wall synthesis

Dose: 250-500 mg q 8 h x 7-10 days

Contraindications: Allergies

Poor renal fxn

Adverse events: GI upset Drug interactions: oral contraceptives

Amoxicillin and clavulanic acid (Augmentin)


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-Lactams

Amino-penicillins

Amoxicillin, ampicillin

Bactericidal ampicillin rash (4-10%)

Spectrum:

Strep, staph, enterococcus, neiseria, treponema, listeria,

E. coli, proteus, H. Flu, shigella, salmonella

Resistance:

Entero, citro, serratia, proteus vulagris, provedincia,

morganella, pseudomonas aeriginosa, acinetobacter


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Cephalosporins

Cephalexin (Keflex)

MOA: Inhibit cell wall synthesis

Dose: 250-1000mg q 6 h x 7-10 days

Contraindications:Allergies

Poor renal fxn

Adverse events: mild GI Drug interactions: probenecid



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Cephalosporins

Cephalexin (Keflex)

Bactericidal

Spectrum: Gram +

Resistance:

Methicillin resistant gram +

Low cross sensitivity with PCN


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LincosamidesLincosamides

Clindamycin (Cleocin)

MOA: binds to the 50S ribosomal subunit and inhibits

protein synthesis

Dose: 100-450mg q 6 h x 7-10 days

Precautions:

Poor hepatic fxn

Adverse events: GI upset, pseudomembraneous

colitis Drug interactions: neuromuscular blocking agents



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Lincosamides

Clindamycin

Bactericidal or static depending on

concentration Spectrum:

Gram +, anaerobes, parasites

Resistance

Enteroccocus

*Clostridium diff. pseudomembranous colitis!!*Clostridium diff. pseudomembranous colitis!!


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Macrolides

Azithromycin (Zithromax), clarithromycin (Biaxin)

MOA: bind to the 23S rRNA in the 50S subunit ribosome

Dose: 250-500 mg/day x 5-10 days

Precautions :

Poor hepatic fxn

Adverse effects: GI

Drug interactions: Cytochrome P-450 (Remember

Seldane?)



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Macrolides

Azithromycin, clarithromycin

Bactericidal

Spectrum: Gram +, gram -, anaerobes

Resistance:

B. fragilis, and strep pneumo


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Tetracyclines

Doxycycline (Vibramycin) MOA: inhibit protein synthesis by preventing aminoacyl

transfer RNA from entering the acceptor sites on the

ribosome Dose: 100mg qd-bid x 7-14 days

Contraindications: Food

pregnancy

Adverse events: GI Drug interactions: anti-epileptics

Pregnancy category D


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Tetracyclines

Doxycycline

Bacteriostatic

Spectrum: Broad, Gram +, -, anaerobes, aerobes, and

spirochetes

Resistance:

Widespread, cross resistance

PHOTO SENSITIVITY!!!


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Nitroimidazoles

Metronidazole (Flagyl)

MOA: reduced intermediate interacts and

breaks the bacterial or parasitic DNA

Dose: 250-1000 mg q 6-8 h x 7-10 days

Precautions : poor hepatic fxn

Adverse events: HA, N/V/D

Drug interactions: EtOH, warfarin, Li+

Pregnancy category D


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Nitroimidazoles

Metronidazole

Bactericidal

Spectrum: Gram - anaerobes

Resistance:

Rare, H. Pylori?

Unpleasant metallic taste


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Fluoroquinolones

Ciprofloxacin (Cipro)

MOA: Inhibition of DNA gyrase, and Topo II

Dose: 250-500 mg qd x 7-10 days Contraindications:


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Fluoroquinolones

Ciprofloxacin

Bactericidal

Spectrum: Very broad except B. frag

Resistance:

MRSA, MRSE


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Antifungals

Nystatin

MOA: inhibit cell wall synthesis

Dose: 5 ml swish and swallow q 4 h x 10-14 d GI upset

Drug interactions: minor

Pregnancy category C


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Antifungals

Clotrimazole (Mycelex), ketoconazole

(Nizoral), fluconazole (Diflucan)

MOA: inhibit cell wall synthesis Dose: 200-800 mg qd x up to 12 months

GI upset

Drug interactions: major p-450 enzyme inhibitor,

interactions with many drugs

Pregnancy category C


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ADA/AAOS AdvisoryADA/AAOS Advisory

StatementStatement

July 1997July 1997


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AAOS StatementAAOS Statement

Antibiotic prophylaxis isAntibiotic prophylaxis is NOTNOT

recommended for dental patientsrecommended for dental patientswithwith plates, pins, or screws,plates, pins, or screws, nor isnor is

it routinely recommended forit routinely recommended for

MOSTMOST dental patients withdental patients with TOTALTOTAL

JOINT REPLACEMENTS.JOINT REPLACEMENTS.


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AAOS recommendationsAAOS recommendations

Prophylaxis recommended

Total joint replacement within the last two years

AND:

Compromised immune system OR

Type 1 DM OR

Previous prosthetic joint infections OR

Malnourishment

OR

Hemophilia


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AAOS recommendations

Prophylaxis antibiotic recommendations Same as AHA OR

No specific regimen recommended

Keflex is often the first drug of choice


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Legal ConsiderationsLegal Considerations

The dentist may not be aware of theThe dentist may not be aware of the

patients medical condition.patients medical condition.

Physician may not be aware of the advisoryPhysician may not be aware of the advisorystatements or of the dental procedure to bestatements or of the dental procedure to be

performed.performed.

Vicarious Liability: The devil made me do itVicarious Liability: The devil made me do it

I forgot to take my antibiotic.I forgot to take my antibiotic.

Documentation.Documentation.


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Legal ConsiderationsLegal Considerations

I forgot my antibiotics!I forgot my antibiotics!

Animal studies have shown antibiotics areAnimal studies have shown antibiotics are

effective up to 2 hours after the procedure.effective up to 2 hours after the procedure. Differentiate between prophylaxis vs.Differentiate between prophylaxis vs.

treatment of an early infection.treatment of an early infection.

Take into consideration patients risk factors.T

ake into consideration patients risk factors. Legal twists.Legal twists.


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In Summary.In Summary.


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Principles of Antibiotic Therapy

Therapeutic effectiveness

Clinical indications Pharmcodynamics, pharmacokinetics

Age and extent of infection


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Patient factors

Age, allergies, compliance, pregnancy risk

Patient function

Renal, hepatic, immunosuppresion, routeapplicability

Cost

Brand name, length of course, alternatives?


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Cost

Drug Name Cost of Therapy $ (~10 Days) Generic if Available

Pen VK 6.81

Amoxicillin 8.41

Ampicillin 12.45

Cephalexin 15.65

Clindamycin 38.45

Azithromycin 41.52

Clarithromycin 74.45

Augmentin 76.82

Doxycycline 5.15

Metronidazole 9.65

Ciprofloxacin 76.65

Nystatin 9.86

Clotrimazole 97.05

Ketoconazole 30.69

Fluconazole 116.25


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Dental Infection

AcuteRapid growth

< 3 daysChronic > 3 days

Pen VK 500mg q6h or

Amox 500mg q8h or

Cephalosporin

Allergic to PCN

Clindamycin 300mg q8h or

Cephalosporin (check allergic Rxn) or

Azith or Clarithromycin

Think Anaerobes

Add Metronidazole 250-500mg

To PCN, Amox, or Ceph

Clindamycin 300mg q8h

antibiotic use in dentistry

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