Interaction between ciprofloxacin and rifampin

OBJECTIVE: To discuss the necessity of dose adjustment for ciprofloxacin or rifampin during their concurrent use. DATA SOURCES: A MEDLINE search (1966-December 1998) was completed using key terms rifampin and fluoroquinolone. English-language journals were conside red, DATA SYNTHESIS: Studies in elderly patients after 14 days of therapy with o ral ciprofloxacin and rifampin did not demonstrate significant differences in the pharmacokinetics of ciprofloxacin as compared with those in patients receiving ciprofloxacin alone. Similar results were found in intravenous d rug abusers. In comparison to the pharmacokinetics of both ciprofloxacin an d rifampin when given alone, the serum bactericidal activity of rifampin, w hen given with ciprofloxacin in healthy elderly volunteers, was reduced but still evident. Ciprofloxacin pharmacodynamics were not significantly alter ed. Serum bacterial titers of ciprofloxacin and pefloxacin increased twofol d when,given with rifampin, although their clinical significance is unknown . RECOMMENDATION : No strong evidence of a significant interaction exists to support dose adjustment for ciprofloxacin or rifampin during their concurre nt use.