FP and MF have similar and very low systemic bioavailability when administered intranasally using a high-dose regimen. It is therefore unlikely that therapeutic doses of intranasal FP or MF will produce dissimilar or significant degrees of systemic exposure or systemic effects.

The pharmacokinetics of five dose levels of lomefloxacin (100, 200, 400, 600, and 800 mg) were examined in a single-dose, double-blind, placebo-controlled study involving 40 subjects. There were eight subjects in each group: five received active drug and three received placebo; each subject was given only one dose. All subjects completed the study, and lomefloxacin was well tolerated at all doses. No drug crystals were noted in the urine at 3 and 6 h after the dose. The mean maximum concentration in serum (Cmax) ranged from 1.11 to 7.46 ,ug/ ml for the 100-to 800-mg doses, respectively, and the AUC increased proportionally with the dose. The mean time to Cmax (Tmax) values averaged 64.8 ± 28.8 min. The elimination half-life and plasma clearance averaged 7.7 ± 0.52 h and 259 ± 37 ml/min, respectively. Mean concentrations in urine were highest during the first 4 h after the dose and ranged from 104 to 713 ,ug/ml following the 100-and 800-mg doses, respectively. Concentrations above 20 ,ug/ml in urine were observed in most subjects over 24 h at the three lower doses and averaged over 120 ,ug/ml during the 12-to 24-h interval at the 400-mg dose, thus supporting once-per-day dosing. Excretion rates from urine and the cumulative amount excreted increased in a dose-related fashion.Renal clearance decreased moderately at the higher doses. Thus, lomefloxacin was well tolerated, and dose proportionality was demonstrated by most pharmacokinetic parameters. The 400-mg dose produced concentrations in plasma and urine above the MIC for susceptible pathogens.

This assay represents a rapid, accurate, and sensitive method for the determination of montelukast in human plasma. The method has been successfully used to demonstrate the bioequivalence of the overcoated montelukast formulations to their equivalent marketed tablets.

Oral ondansetron is an effective therapy for the prevention of emesis induced by TBI.