Dose-dependent pharmacokinetic study of pefloxacin, a new antibacterial agent, in humans.

A dose-dependent pharmacokinetic study of pefloxacin was performed after four intravenous infusions and four orally administered doses. After intravenous infusion, the pharmacokinetic profiles of the plasma concentrations showed a biphasic decline, with half-lives (mean +/- SD) of 8.55 +/- 4.20 min and 11.50 +/- 1.75 h, respectively. Intravenous infusion and oral administration yielded similar results. The pharmacokinetic parameters remained constant in the dose range of 200-800 mg from the plasma and urine data.