Interaction between ciprofloxacin and rifampin.

Area of Science:

• Pharmacology and Drug Interactions
• Infectious Diseases

Background:

• Ciprofloxacin, a fluoroquinolone antibiotic, and rifampin, an antibiotic used to treat tuberculosis, are sometimes prescribed concurrently.
• Understanding potential drug interactions is crucial for optimizing patient outcomes and ensuring therapeutic efficacy.

Purpose of the Study:

• To evaluate the necessity of adjusting dosages when ciprofloxacin and rifampin are administered together.
• To assess the impact of concurrent administration on the pharmacokinetic and pharmacodynamic profiles of both drugs.

Main Methods:

• A comprehensive literature search of MEDLINE (1966-December 1998) was conducted using keywords 'rifampin' and 'fluoroquinolone'.
• English-language studies were included in the review.

Main Results:

• No significant pharmacokinetic differences in ciprofloxacin were observed in elderly patients or intravenous drug abusers receiving concurrent therapy compared to ciprofloxacin alone.
• While serum bactericidal activity of rifampin was reduced but remained evident when co-administered with ciprofloxacin in elderly volunteers, ciprofloxacin pharmacodynamics were not significantly altered.
• A twofold increase in serum bacterial titers for ciprofloxacin and pefloxacin was noted with rifampin, though clinical significance remains undetermined.

Conclusions:

• Current evidence does not strongly support the need for dose adjustments for ciprofloxacin or rifampin when used concurrently.
• Further research may be warranted to clarify the clinical implications of observed changes in serum bacterial titers.