Comparison of in vitro dissolution results of the enteric-coaled tablets of indometacin from 6 pharmaceutical factories

Objective: To investigate the in vitro dissolution results of enteric-coaled tablets of indometacin probided by 6 different drug manufacturers.Methods: The dissolution tests were carried out with the rotating basket.The ultraviolet spectrometric assay was used to determine the concentration of indometacin in dissolution media.The cumulative dissolution percent of the labeled amount was calculated and the Weibull's equation was used to model the main dissolution parameters according to the dissolution data.The differences between different groups were statistically analysed.Results: The dissolution data of the indometacin tablets produced by different manufacturers meet the requirements of pharmacopoeia in the dissolution test with acidic medium(0.1 mol/L HCL),but one kind of indometacin tablet failed to meet the requirements of pharmacopoeia in the dissolution test with pH 6.8 phosphate buffer solution.Conclusions: The dissolution parameters of the enteric-coated tablets of indometacin from 6 different manifactures differ greatly.