The study of the bioavailability of coated acetylsalicylic acid in suppositories after rectal administration.

The rate of release of acetylsalicylic acid (ASA) coated and uncoated from suppositories in vitro, and the bioavailability of ASA in vivo were examined. The coating reduces the rate of release of activite drug from suppositories. In vivo the coating delays the obtention of the maximum concentration of salicylates in urine, but doesn't have any essential effect on cummulative amount of salicylates in urine.