What is the recommended dosage of amoxicillin (amoxicillin) for dental prophylaxis?

Amoxicillin Dosage for Dental Prophylaxis

For adults, administer a single dose of 2 grams of amoxicillin orally, taken 30-60 minutes before the dental procedure; for children, the dose is 50 mg/kg (not to exceed the adult dose). 1, 2

Standard Dosing Regimen

Adults

• Amoxicillin 2 g orally as a single dose, administered 30-60 minutes before the procedure 1, 3
• This dose provides adequate serum levels that remain substantially higher than the minimum inhibitory concentrations (MICs) for oral streptococci for at least 6 hours after administration 4

Pediatric Patients

• Amoxicillin 50 mg/kg orally as a single dose, administered 30-60 minutes before the procedure 1
• The total pediatric dose should not exceed the adult dose of 2 g 1

Who Requires Prophylaxis

Antibiotic prophylaxis should only be prescribed for patients at highest risk for infective endocarditis undergoing at-risk dental procedures. 1 The highest-risk cardiac conditions include:

• Prosthetic cardiac valve or prosthetic material used for cardiac valve repair 1, 3
• Previous history of infective endocarditis 1, 3
• Unrepaired cyanotic congenital heart disease (CHD), including palliative shunts and conduits 1, 3
• Completely repaired CHD with prosthetic material or device during the first 6 months after the procedure 1, 3
• Repaired CHD with residual defects at or adjacent to the site of a prosthetic patch or device 1, 3
• Cardiac transplant recipients who develop cardiac valvulopathy 1, 3

At-Risk Dental Procedures

Prophylaxis is indicated only for dental procedures that involve manipulation of gingival tissue, manipulation of the periapical region of teeth, or perforation of the oral mucosa. 1, 2 This includes:

• Scaling and root planing 2
• Endodontic (root canal) procedures 2
• Tooth extractions 1
• Periodontal surgery 1

Prophylaxis is NOT required for:

• Routine anesthetic injections through noninfected tissue 2, 5
• Taking dental radiographs 2, 5
• Placement or adjustment of removable prosthodontic or orthodontic appliances 1
• Shedding of deciduous teeth 1
• Treatment of superficial caries 1

Alternative Regimens for Penicillin Allergy

For Patients Able to Take Oral Medications

• Clindamycin 600 mg orally, 30-60 minutes before the procedure 1, 2, 5
• Alternatively: Cephalexin 2 g orally (only if no history of anaphylaxis, angioedema, or urticaria with penicillin) 1
• Alternatively: Azithromycin or clarithromycin 500 mg orally (adults) or 15 mg/kg (children) 1

For Patients Unable to Take Oral Medications

• Ampicillin 2 g IV or IM (adults) or 50 mg/kg IV or IM (children), administered within 30 minutes before the procedure 1, 2
• Alternatively: Cefazolin or ceftriaxone 1 g IV or IM (adults) or 50 mg/kg IV or IM (children) 1
• Alternatively: Clindamycin 600 mg IV or IM (adults) or 20 mg/kg IV or IM (children) 1

Critical caveat: Cephalosporins should NOT be used in patients with a history of anaphylaxis, angioedema, or urticaria with penicillins due to cross-sensitivity. 1, 3

Important Clinical Considerations

Single Dose Only

Only a single pre-procedure dose is indicated; post-procedure antibiotics are NOT recommended for prophylaxis. 2 Research demonstrates that adding a 2-day postoperative course of amoxicillin provides no additional benefit over a single preoperative dose for implant placement, while adverse events (including one severe allergic reaction requiring hospitalization) occurred only in the postoperative antibiotic group 6

Patients Already on Antibiotics

For patients already receiving long-term antibiotic therapy, select an antibiotic from a different class rather than increasing the dosage of the current antibiotic. 2, 3

Route of Administration

For patients on anticoagulants, oral administration is strongly preferred over intramuscular injections to avoid hematoma formation. 2, 3

Common Pitfalls to Avoid

The vast majority (80.9%) of antibiotic prophylaxis prescriptions before dental visits are unnecessary according to current guidelines. 7 Common errors include:

• Prescribing prophylaxis for patients with prosthetic joints (not indicated per current evidence) 5
• Prescribing prophylaxis for patients with mitral valve prolapse without other high-risk features 2
• Prescribing prophylaxis for low-risk dental procedures that don't manipulate gingival tissue 1, 2
• Prescribing prolonged courses when only a single dose is indicated 2

The most important preventive measure is maintaining excellent oral hygiene, which reduces bacteremia from daily activities (tooth brushing, chewing) that far exceed the bacteremia risk from dental procedures. 1, 2, 5

Evidence Quality Note

While some research suggests that 3 g of amoxicillin may be marginally more effective than 2 g for implant procedures 8, 9, the established guideline recommendation from the American Heart Association and European Society of Cardiology remains 2 g for adults, which provides adequate serum levels and has 50 years of safe use without reported fatal anaphylaxis when used as recommended 1, 4