In vitro antimicrobial effects of various combinations of penicillin and clindamycin against four strains of Streptococcus pyogenes.

Abstract

Previous studies using mouse models of Streptococcus pyogenes necrotizing fasciitis demonstrated that clindamycin had greater efficacy than penicillin. Frequently both agents are used concurrently in the treatment of severe S. pyogenes infections. This study investigated interactions between penicillin and clindamycin. E-test and broth microdilution assays suggested additivity or indifference, while timed-killing assays demonstrated concentration-dependent variable effects. Timed-kill studies utilizing clinical concentrations suggest that there is no antagonism with the combination of drugs but that the combination does not have a bactericidal advantage over either penicillin or clindamycin alone.

• Authors: D L Stevens, K J Madaras-Kelly, D M Richards
• Journal: Antimicrobial agents and chemotherapy (Antimicrob Agents Chemother) Vol. 42 Issue 5 Pg. 1266-8 (May 1998) ISSN: 0066-4804 [Print] United States
• PMID: 9593164 (Publication Type: Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Penicillins
• Clindamycin

Topics

• Clindamycin (pharmacology)
• Colony Count, Microbial
• Drug Interactions
• Drug Therapy, Combination (pharmacology)
• Microbial Sensitivity Tests
• Penicillins (pharmacology)
• Streptococcus pyogenes (drug effects)