In vitro assessment of the effect of clavulanic acid at concentrations achieved in human serum on the bactericidal activity of amoxicillin at physiological concentrations against Staphylococcus aureus: implications for dosage regimens

Antimicrob Agents Chemother. 1997 Jun;41(6):1403-5. doi: 10.1128/AAC.41.6.1403.

Abstract

The effects on Staphylococcus aureus viability and beta-lactamase activity of concentrations that simulated those in human serum after a combined dose of 875 mg of amoxicillin and 125 mg of clavulanic acid were studied in an in vitro pharmacodynamic model. Six hours of preexposure to concentrations of the amoxicillin-clavulanic acid combination that were higher than the amoxicillin-clavulanic acid MIC led to a reduction of the initial inoculum of >90% and to a significant decrease of beta-lactamase activity versus those of the control even from 6 h, when concentrations were subinhibitory. The postantibiotic effect and post-beta-lactamase inhibitor effect contributed to these results.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amoxicillin / blood
  • Amoxicillin / pharmacology*
  • Amoxicillin-Potassium Clavulanate Combination
  • Anti-Bacterial Agents / blood
  • Anti-Bacterial Agents / pharmacology*
  • Clavulanic Acid
  • Clavulanic Acids / blood
  • Clavulanic Acids / pharmacology*
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Drug Therapy, Combination / blood
  • Drug Therapy, Combination / pharmacology*
  • Humans
  • Kinetics
  • Penicillins / blood
  • Penicillins / pharmacology*
  • Serum Bactericidal Test
  • Staphylococcus aureus / drug effects*
  • Staphylococcus aureus / enzymology
  • beta-Lactamases / metabolism

Substances

  • Anti-Bacterial Agents
  • Clavulanic Acids
  • Penicillins
  • Clavulanic Acid
  • Amoxicillin-Potassium Clavulanate Combination
  • Amoxicillin
  • beta-Lactamases