Pharmacokinetics and safety of high-dose and extended-interval regimens oflevofloxacin in human immunodeficiency virus-infected patients

The pharmacokinetics of levofloxacin, administered in high doses and with e xtended dosing intervals, was studied in human immunodeficiency virus (HIV) -infected patients. Thirty patients received either 750 mg of the drug or a placebo once daily for 14 days, followed by 750 mg or 1,000 mg of the drug or a placebo three times weekly for an additional 14 days. Levofloxacin di sposition was characterized by rapid oral absorption, with peak concentrati ons occurring approximately 1.5 h after dosing and elimination half-lives f rom 7.2 to 9.4 h. The overall incidence of any adverse effect was 70% (1,00 0 mg) to 95% (750 mg) for levofloxacin-treated patients and 71% for those t aking the placebo. Levofloxacin pharmacokinetic parameters for HIV-infected patients were consistent with those observed in studies of healthy volunte ers.