Effect of aging on physical properties of phenylbutazone tablets

A study was made of the influence of age on the physical properties of phenylbutazone tablets BP, with special reference to in vitro dissolution rates. Past batches of tablets showed a progressive decrease in dissolution rate with age. This effect could be simulated in short periods by using elevated temperatures. The effect appears to be connected with the subcoat layer of the sugar coating of the tablet which adheres more strongly to the tablet core and slows down its disintegration.