The pharmacokinetics and bioavailability of rabeprazole following single intravenous infusion and oral administration in healthy Chinese volunteers

To investigate the pharmacokinetics and bioavailability of rabeprazole administrated by intravenous infusion and oral administration in healthy Chinese volunteers. A total of 20 male subjects were recruited and randomly assigned at the beginning of the study to receive a single dose of rabeprazole (20 mg) administrated either intravenously or orally. Following a 7-day washout period, all subjects received another 20mg dose via the alternate route. Intravenous dose was given in constant infusion over 30 min, and the oral dose was given in two 10mg tablets. Intravenous administration yielded the following measurements: the terminal half-life was (62.4±10.7) min; the Cmax was (1308.6±266.4) ng·ml-1; the total body clearance was (0.21±0.05) L·min-1; the AUC0-τ and AUC0-∞ were (99.6±21.9) mg∙min∙L-1 and (102. 4±23.3) mg∙min∙L-1, respectively. Oral administration yielded the following measurements: the half-life was (64.2±15.5) min; the Cmax was (508.3±180.2) ng·ml-1; Tmax was attained at about 229.5 min; the total body clearance was (0.31±0.10) L·min-1; the AUC0-τ and AUC0-∞ were (69.5±20.0) mg∙min∙L-1 and (70.6±20.2) mg∙min∙L-1, respectively. The bioavailability of rabeprazole was estimated to be 70.1% in healthy Chinese volunteers. The total body clearance after oral administration was significantly higher than that measured following intravenous administration (P <0.01).