Increased gastro-intestinal absorption of hexobarbital by hydrophilization

Abstract

This paper reports a comparative evaluation of thein vivo andin vitro availability of pure and hydrophilised hexobarbital from capsules. Hydrophilization of the poorly soluble hydrophobic drug was performed by coating the powder particles with hydrophilic methylcellulose. Liquid penetration into plugs of the treated powder, disintegration times andin vitro release rates became independent of the liquid wetting potency and were extremely fast compared with the pure drug. A bioavailability study in eight healthy volunteers showed a strongly increased extent and rate of absorption of the treated drug compared with the pure drug. The absorption rate of the hydrophilised free acid of hexobarbital was almost as rapid as that of the sodium salt.