Keywords: 
• metformin hydrochloride /
• tablets /
• dissolution

Abstract: Objective :To compare the dissolution of metformin hydrochloride tablets in vitro from fifteen different pharmaceutical factories and provide suggestions for clinical application. Methods :The dissolution tests were carried out with rotating basket.UV method was used to determine the concentration of metformin hydrochloride.The accumulative dissolution based on the labeled amount was calculated and the Weibull's equation was used to model the dissolution parameters.The difference between different groups was statistically evaluated by variance analysis. Results :The dissolution of metformin hydrochloride tablets in vitro from fifteen different pharmaceutical factories conformed to the requirements of Chinese Pharmacopoeia (2005).But significant difference was found among the metformin hydrochloride tablets from fifteen different pharmaceutical factories in dissolution parameter m,T₃₀,T₅₀,T_d and T₈₀ (P< 0.01). Conclusion :There was significant difference in dissolution parameters among the metformin hydrochloride tablets from fifteen different pharmaceutical factories.It was indicated that attention should be paid to their clinical application.