Effect of gender on the pharmacokinetics of ofloxacin

To assess the influence of gender on the pharmacokinetics of ofloxacin.

Open-label study.

Academic medical center.

Five healthy men and seven healthy women volunteers.

Subjects received a single oral dose of ofloxacin 400 mg, and serial blood samples were collected for 24 hours. Plasma concentrations of ofloxacin were determined by high-performance liquid chromatography and pharmacokinetic parameters were determined. Statistical comparisons between genders were made with the Wilcoxon rank sum test.

Median volume of distribution at steady state/systemic bioavailability (V(ss)/F) was significantly smaller in women than in men, although when normalized for total body weight there were no differences. Except for terminal elimination half-life, which was 10% shorter in women, no other pharmacokinetic values were significantly different between genders. Median peak concentrations, although not statistically different, were 28% higher in women.

Ofloxacin V(ss)/F values were smaller in women than in men, explained by gender-related differences in weight.