Simultaneous Formulation, Estimation and Evaluation of Allopurinol Sustained Release Tablets using Various Suitable Excipients

The present investigation an attempt has been made to increase therapeutic efficacy, reduce frequency of administration and improve patient compliance, by developing sustained release matrix tablets of Allopurinol. Sustained release matrix tablets of Allopurinol, were developed by using different drug: polymer ratio. Kollidon SR, Hydroxypropyl methylcellulose K15M, K100M as matrix former. All lubricated formulations were compressed by direct compression and by wet granulation method. Compressed tablets were evaluated for uniformity of weight, content of active ingredient, friability, hardness, thickness, in vitro dissolution, and swelling index. All the formulation showed compliance with pharmacopoeial standards. Among the different formulation, B8 showed sustained release of drug for 12 hours with 86.55% release. The regression coefficient value of Higuchi plot was found to be 0.9925 that showed that drug was released by diffusion mechanism. The slope value of korsmeyer ‐peppas equation was found to be 0.5062 which indicating that drug was released by non‐fickian release mechanism. The R2 value for Hixson Crowell plot was found to be 0.9919 which indicates that drug release was limited by drug particle dissolution rate and erosion of the polymer matrix. Thus, drug in combination with Hydroxy propyl methyl cellulose K100M were found to be effective in retarding the release of Allopurinol.