Pharmacokinetics and bioequivalence of domperidone orally disintegrating tablets in healthy volunteers

OBJECTIVE To determine domperidone in human plasma by LC-MS/MS method,and to investigate its pharmacokinetics and relative bioavailability.METHODS Domperidone concentrations in plasma extracted with being precipitated protein by methanol were determinated by LC-MS/MS.The test formulations(domperidone orally disintegrating tablets)and reference formulations(domperidone tablets) were given to 18 healthy male volunteers.The pharmacokinetics of test formulations(domperidone orally disin-tegrating tablets) and reference formulations and the bioequivalence of the two formulations were evaluated.RESULTS The calibration curve was linear within the range of 0.100-50 ng·mL-1.The method recovery was 79.2%-87.8%.RSDs of intra-day and inter-day were less than 15%.After a single oral dose of 10 mg the test or reference formulations,the main pharmacokinetic parameters were as follows: Cmax(20.5±7.6) and(15.8±6.1) ng·mL-1;tmax(0.79±0.21) and(0.68±0.31)h;t1/2(9.92±2.02) and(9.50±1.61)h;AUC(0-36)(84.3±26.2) and(71.0±15.0)h·ng·mL-1;AUC(0-∞)(89.8±28.2) and(74.6±16.4)h·ng·mL-1,respectively.Relative bioavailability was(113.5±10.3)%.CONCLUSION The method was sensitive with no endogenous interference.No significant difference exists among the main pharmacokinetic parameters for the test and reference tablets.The two formulations are bioequivalence.