The relative bioavailability and bioequivalence assessment of domestic terazosin in healthy volunteers

Objective:The pharmacokinetics and pharmacodynamics of terazosin domestic capsules and imported tablets in 9 normal male healthy volunteers were studied. Method: Drug concentration in plasma was determined by HPLC. Results: The plasma concentration time curve of the domestic capsules and imported tablets were all fitted to two compartment model. ρ max were (41±11) and (44±10) μg·L -1 ; t max (0.8±0.4) and (0.7±0.5) h; t 1/2 (12±4) and (9.0±1.6) h; AUC 0 ∝ (405±106) and (398±90) μg·h·L -1 , respectively. The relative bioavailability of domestic capsules was 104.43%. The study of pharmacodynamics revealed blood pressure reduced lightly, and there was no significant changes in the heart rate of two preparations .The statistical analysis showed that there was no significant difference between the two preparations ( P 0.05). Conclusion: (1) F of terazosin capsules was 104.43%. (2) Domestic capsules and imported tablets were bioequivalent. (3) There were no significant changes in the blood pressure and heard rate in normal male volunteers after a single oral dose (2 mg) of two terazosin preparations.