HPLC-MS determination of pharmacokinetic of ondansetron in human plasma and its bioequivalence

Objectives:To establish an HPLC-MS method for determination of pharmacokinetic of ondansetron in human plasma,and to study the bioequivalence of ondansetron hydrochloride oral solution.Methods:Twenty healthy male volunteers were orally administered with a randomized and single crossover dose of ondansetron hydrochloride oral solution(test sample) and ondansetron hydrochloride tablets(reference sample)8 mg.The plasma ondansetron were quantified by HPLC-MS(SIM+).The pharmacokinetics parameters and relative bioavailability were calculated using DAS 2.0.Results:The main pharmacokinetic parameters of test and reference preparation were as followed: tmax were(1.65±0.46)h and(1.60±0.62) h,Cmax were(57.58±14.11)ng·mL-1 and(53.01±16.24)ng·mL-1,t1/2 were(3.50±0.80)h and(4.13±1.25)h,AUC(0→24)were(353.63±75.84)ng·h·mL-1 and(326.02±104.49)ng·h·mL-1.Conclusion:The results show that the two formulations are bioequivalent.The relative bioavailability of ondansetron hydrochloride oral solution is 110.9%.