What is the recommended amoxicillin dose (and alternatives) for antibiotic prophylaxis before a dental procedure in patients requiring infective endocarditis prevention, including dosing for adults, children, renal impairment, and penicillin allergy?

Amoxicillin Prophylaxis for Dental Procedures

For adults requiring infective endocarditis prophylaxis before dental procedures, give amoxicillin 2 grams orally as a single dose 30-60 minutes (or 1 hour) before the procedure. 1, 2, 3, 4

Standard Dosing Regimens

Adults (Non-Allergic to Penicillin)

• Amoxicillin 2 g orally taken 30-60 minutes before the dental procedure 1, 2, 3, 4
• This is a single dose only—no post-procedure antibiotics are needed 2, 3, 4

Pediatric Patients (Non-Allergic to Penicillin)

• Amoxicillin 50 mg/kg orally (maximum 2 g) taken 30-60 minutes before the procedure 1, 2
• The total pediatric dose must never exceed the adult maximum of 2 g 1

Patients Unable to Take Oral Medications

• Ampicillin 2 g IM or IV within 30 minutes before the procedure (adults) 1, 3, 4
• Ampicillin 50 mg/kg IM or IV within 30 minutes before the procedure (children, maximum 2 g) 1

Alternative Regimens for Penicillin Allergy

Oral Alternatives (Penicillin-Allergic Patients)

• Clindamycin 600 mg orally 30-60 minutes before the procedure is the preferred alternative for all penicillin-allergic patients 1, 2, 3, 4
• Cephalexin 2 g orally may be used ONLY if there is no history of anaphylaxis, angioedema, or urticaria with penicillin 1, 2
• Azithromycin or clarithromycin 500 mg orally are additional options 1, 4

Pediatric Penicillin-Allergic Patients (Oral)

• Clindamycin 20 mg/kg orally (maximum 600 mg) 30-60 minutes before the procedure 1, 2
• Cephalexin 50 mg/kg orally (maximum 2 g) if no immediate-type hypersensitivity to penicillin 1

IV Alternatives (Penicillin-Allergic, Cannot Take Oral)

• Clindamycin 600 mg IV within 30 minutes before the procedure (adults) 1, 2
• Clindamycin 20 mg/kg IV (maximum 600 mg) within 30 minutes before the procedure (children) 1, 2
• Cefazolin 1 g IM or IV within 30 minutes (adults, only if no immediate-type hypersensitivity) 1
• Cefazolin 25 mg/kg IM or IV within 30 minutes (children, maximum 1 g, only if no immediate-type hypersensitivity) 1
• Vancomycin 1 g IV over 1-2 hours, completed within 30 minutes of starting the procedure (adults) 4

Special Clinical Situations

Patients Already on Chronic Antibiotics

• Select an antibiotic from a different class rather than increasing the dose of the current antibiotic 2, 3, 4
• If the patient is on long-term penicillin, use clindamycin, azithromycin, or clarithromycin instead 2
• Avoid cephalosporins in patients on chronic penicillin due to possible cross-resistance 2

Patients on Anticoagulation

• Use oral regimens exclusively—avoid intramuscular injections entirely 2, 3, 4
• If IV administration is necessary, use IV ampicillin or clindamycin 1

Patients on Hemodialysis

• The standard 2 g amoxicillin dose remains appropriate despite renal impairment if not allergic to penicillin 2, 3
• No dose adjustment is required for single-dose prophylaxis 2

Critical Timing and Duration

• Only a single pre-procedure dose is indicated—post-procedure antibiotics are NOT recommended for prophylaxis 2, 3, 4
• Timing is 30-60 minutes (or 1 hour) before the procedure for oral regimens 1, 2, 3, 4
• Timing is within 30 minutes before the procedure for IV/IM regimens 1, 2

Common Pitfalls and How to Avoid Them

Do NOT Prescribe Prolonged Antibiotic Courses

• A single preoperative dose is sufficient—prolonged courses only increase adverse event risk without additional benefit 4
• This is one of the most common errors in prophylaxis prescribing 3, 4

Do NOT Use Cephalosporins in Immediate-Type Hypersensitivity

• Cephalosporins (cephalexin, cefazolin, cefadroxil) are contraindicated in patients with a history of anaphylaxis, angioedema, or urticaria to penicillins 1, 2, 4
• Even though actual cross-reactivity rates are low (1-5%), the risk is unacceptable in this setting 2

Do NOT Give IM Injections to Anticoagulated Patients

• Oral or IV routes must be used instead 2, 3, 4

Do NOT Increase Current Antibiotic Dose

• If a patient is already on antibiotics, switch to a different class rather than increasing the dosage 2, 3, 4

Recognize That Most Patients Do NOT Need Prophylaxis

• Prophylaxis should only be prescribed for patients with highest-risk cardiac conditions, not for all dental patients 3, 4
• Maintaining good oral hygiene is more important for preventing infective endocarditis than antibiotic prophylaxis 3