What is the recommended dose of amoxicillin for dental prophylaxis?

Amoxicillin Dental Prophylaxis Dosing

For adults requiring endocarditis prophylaxis before dental procedures, administer 2 grams of amoxicillin orally as a single dose 30-60 minutes before the procedure. 1, 2, 3

Standard Dosing Regimens

Adults

• Oral route (preferred): 2 g amoxicillin orally, single dose 30-60 minutes before procedure 1, 3
• Unable to take oral medications: Ampicillin 2 g IM or IV within 30 minutes before procedure 1, 3

Pediatric Patients (≥3 months old)

• Oral route: 50 mg/kg (maximum 2 g) as single dose 30-60 minutes before procedure 1
• Unable to take oral medications: Ampicillin 50 mg/kg IM or IV within 30 minutes before procedure 1

Penicillin Allergy Alternatives

For Adults with Penicillin Allergy

• Clindamycin: 600 mg orally 1 hour before procedure 1, 3
• Azithromycin or clarithromycin: 500 mg orally 1 hour before procedure 1, 3
• Cephalexin: 2 g orally (only if no history of anaphylaxis, angioedema, or urticaria with penicillins) 1

For Pediatric Patients with Penicillin Allergy

• Clindamycin: 20 mg/kg orally 1 hour before procedure 1
• Azithromycin or clarithromycin: 15 mg/kg orally 1 hour before procedure 1
• Cephalexin: 50 mg/kg orally (only if no immediate-type hypersensitivity) 1

High-Risk Cardiac Conditions Requiring Prophylaxis

Prophylaxis is ONLY indicated for patients with the highest-risk cardiac conditions: 1, 2, 3

• Prosthetic cardiac valves or prosthetic material used for valve repair 1, 3
• Previous history of infective endocarditis 1, 3
• Specific congenital heart diseases:
  • Unrepaired cyanotic CHD, including palliative shunts and conduits 1
  • Completely repaired CHD with prosthetic material during first 6 months post-procedure 1
  • Repaired CHD with residual defects at or adjacent to prosthetic patch/device site 1
• Cardiac transplant recipients who develop cardiac valvulopathy 1, 3

Important: Patients with mitral valve prolapse, rheumatic heart disease without prosthetic valves, and other moderate-risk conditions do NOT require prophylaxis 2, 3

Dental Procedures Requiring Prophylaxis

Prophylaxis is indicated for procedures involving: 1, 2, 3

• Manipulation of gingival tissue (e.g., scaling, root planing) 2, 3
• Manipulation of periapical region of teeth (e.g., endodontic treatment) 2, 3
• Perforation of oral mucosa 1, 3
• Dental extractions 3
• Dental implant placement 3

Prophylaxis is NOT required for: 2, 4, 3

• Routine anesthetic injections through noninfected tissue 2, 4, 3
• Taking dental radiographs 2, 4, 3
• Placement of orthodontic brackets 3

Critical Special Considerations

Patients on Chronic Antibiotic Therapy

• Select an antibiotic from a different class rather than increasing the dosage of the current antibiotic 2, 3

Patients on Anticoagulation

• Avoid intramuscular injections—use oral regimens whenever possible 2, 3

Patients on Hemodialysis

• Standard 2 g amoxicillin dose remains appropriate if not allergic to penicillin 2, 4

Renal Impairment

• No dose adjustment needed unless GFR <30 mL/min 5
• For severe renal impairment (GFR <30 mL/min), standard prophylaxis dosing may need adjustment for therapeutic indications, but single prophylactic doses are generally well-tolerated 5

Common Pitfalls to Avoid

• Do NOT prescribe prophylaxis for all dental patients—restrict to highest-risk cardiac conditions only 2, 3
• Do NOT prescribe prolonged courses—a single preoperative dose is sufficient; postoperative antibiotics are not recommended and only increase adverse event risk 2, 3, 6
• Do NOT use cephalosporins in patients with immediate-type penicillin hypersensitivity (anaphylaxis, angioedema, urticaria) 1, 3
• Do NOT use IM injections in anticoagulated patients 2, 3
• Do NOT forget that maintaining good oral hygiene is more important than prophylaxis for preventing endocarditis—most cases result from randomly occurring bacteremias from daily activities rather than dental procedures 2, 3

Evidence Quality Notes

The 2007 American Heart Association guidelines represent a major paradigm shift, acknowledging that antibiotic prophylaxis prevents only an extremely small number of infective endocarditis cases, even if 100% effective 1, 3. The recommendation for routine prophylaxis is reasonable only for patients with the highest-risk cardiac conditions 1. Research evidence comparing 2 g versus 3 g preoperative doses for implant procedures suggests 3 g may be marginally more effective, but the 2 g dose remains the guideline-recommended standard for endocarditis prophylaxis 1, 7, 8.