Activity of clarithromycin and its principal human metabolite against Haemophilus influenzae

J. H. Jorgensen, L. A. Maher, A. W. Howell

Research output: Contribution to journalArticle

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Clarithromycin is a new macrolide antibiotic which forms a microbiologically active principal in vivo metabolite, 14-OH-clarithromycin. The in vitro activities of clarithromycin and its metabolite were examined separately and in pharmacokinetically relevant fixed combinations of 4:1 and 2:1 against a group of 50 Haemophilus influenzae isolates. Broth microdilution susceptibility tests indicated that clarithromycin was less active than erythromycin against all but highly erythromycin-susceptible strains, while 14-OH-clarithromycin was generally more active than either antibiotic. An enhancement in activity against the majority of strains was demonstrated when clarithromycin and its metabolite were tested in combination.

Original languageEnglish (US)
Pages (from-to)1524-1526
Number of pages3
JournalAntimicrobial agents and chemotherapy
Issue number7
Publication statusPublished - Jan 1 1991


ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)
  • Infectious Diseases

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