OBJECTIVE:To prepare tamsulosin hydrochloride sustained-released tablets and to investigate the in vitro drug release feature and mechanism of the tablets.METHODS:Tamsulosin hydrochloride sustained-released tablets were prepared with HPMC as matrix.The effects of multiple factors on the in vitro drug release rate were evaluated with accumulative release rate as index,and the slow release feature was compared between the sustained tablets and the common tablets.RESULTS:The drug release rate was predominantly influenced by the amount of HPMC and the tablet compressing pressure,and the optimum values of the two were 25% and 8kg～11kg,respectively.The accumulative release rates of the sustained tablets and the common tablets at 0.5h were 10% and 50%,respectively.CONCLUSIONS:The sustained-release tablets had a better sustained release efficacy as compared with common tablets,and the drug release feature of the sustained tablets was the synergistic action of the tamsulosin hydrochloride diffusion and matrix degradation and the release pattern obeyed non-Fick diffusion mechanism.