The clinical pharmacokinetics of osmotic pump controlled release tablets of terazosin hydrochloride in healthy volunteers was studied.A sensitive and rapid HPLC method was used to determine the terazosin plasma concentrations,and single and multiple doses of terazosin hydrochloride regular tablets（reference tablets）and osmotic pump controlled release tablets were orally administrated in randomized crossover design.The results showed that the C_（max）of the reference tablets after single oral dose（（120.56±23.15）ng/mL）in 20 healthy volunteers was significantly higher than that of controlled release tablets （（95.27±16.35）ng/mL）.The T_（max）of the controlled release tablets（（2.65±0.82）h）was significantly longer than that of reference tablets（（1.27±0.61）h）（P0.05）.The relative bioavailability of the controlled release tablets was found to be（105.85±6.12）%. The multiple oral dose pharmacokinetic parameters of the regular tablets and controlled release tablets were as follows：AUC_（SS） were（1275.17±175.35）and（1382.65±205.31）ng·h/mL respectively,C_（max）were（128.15±22.37）and（98.57±18.16）ng/mL respectively,T_（max）were（1.35±0.71）and（2.76±0.85）h respectively,C_（av）were（53.13±9.12）and（57.61±9.25）ng/mL respectively, and DF were（2.25±0.26）%and（1.62±0.25）%respectively.The relative bioavailability of the controlled release tablets to the reference tablets was（108.43±6.26）%.The controlled release tablet of terazosin hydrochloride was bioequivalent to the reference tablet.The controlled release tablet exhibited a sustained-release property with a significantly longer T_（max）and lower C_（max）.
