Oral amoxicillin as prophylaxis for endocarditis: what is the optimal dose?

Clin Infect Dis. 1994 Feb;18(2):157-60. doi: 10.1093/clinids/18.2.157.

Abstract

We compared serum levels and tolerability of oral amoxicillin in 30 healthy adults who each received 2.0 g of amoxicillin and, 1 week later, 3.0 g of the same preparation. Serum levels of amoxicillin were determined at 1, 2, 4, and 6 hours following its ingestion. Mean serum levels of amoxicillin were significantly higher after 3.0-g doses than after 2.0-g doses. Levels in females were higher than in males; this was a reflection of differences in body weights. Food intake had no effect on serum levels. The 2.0-g doses resulted in adequate serum levels; 6 hours after dosing levels were still substantially higher than the MICs for oral streptococci. Three individuals (10%) experienced mild gastrointestinal side effects after they received the 3.0-g doses; no side effects were noted after the 2.0-g doses. We propose that to prevent bacterial endocarditis in adults who are at risk, a single 2.0-g dose of oral amoxicillin may be adequate prophylaxis for dental, oral, or upper respiratory tract procedures.

Publication types

  • Comparative Study

MeSH terms

  • Administration, Oral
  • Adult
  • Amoxicillin / administration & dosage*
  • Amoxicillin / adverse effects
  • Amoxicillin / blood
  • Digestive System / drug effects
  • Dose-Response Relationship, Drug
  • Drug Tolerance
  • Endocarditis, Bacterial / prevention & control*
  • Female
  • Humans
  • Male

Substances

  • Amoxicillin