Effect of Itraconazole on the Pharmacokinetics of Ciprofloxacin in Healthy Volunteers

Abstract

Itraconazole, a triazole antifungal agent, is a potent cytochrome P-450 inhibitor and
also a P-glycoprotein (P-gp) inhibitor. Ciprofloxacin, a fluoroquinolone compound with
broad spectrum antimicrobial activity, is often coadministered with an antifungal drug in
HIV-infected patients. The drug-drug interaction between itraconazole and ciprofloxacin may
occur in these patients. Therefore, the aim of this study was to investigate the effect of
itraconazole on the pharmacokinetics of ciprofloxacin following a multiple oral dose in
healthy volunteers. Two-phase crossover study with a 2 week washout period was designed
to study in six healthy volunteers. In phase 1, each volunteer received 500 mg of
ciprofloxacin twice daily for 7 days whereas in phase 2, they also received 500 mg
ciprofloxacin and 200 mg itraconazole twice daily for 7 days. The results revealed that there
was no significant difference in each ciprofloxacin pharmacokinetic parameter between 2
phases of study in six healthy volunteers. In conclusion, itraconazole co-administration with
ciprofloxacin did not alter the ciprofloxacin pharmacokinetics in healthy volunteers.