Bioavailability of hydrocortisone retention enemas in relation to absorption kinetics

Abstract

The rate and extent of absorption of hydrocortisone from 2 commercial formulations of rectal enemas were determined in 12 normal subjects. The bioavailability of the enema was related to its absorption rate constant. Subjects (4) absorbed hydrocortisone slowly from both enemas at a mean rate of 0.361/h and 5 subjects absorbed hydrocortisone rapidly from both preparations at a mean rate of 1.05/h (P < 0.001). The bioavailability of hydrocortisone retention enemas was 0.810 and 0.502 in slow and rapid absorbers (P < 0.01).