THe Incorporation and in Vitro Release Profiles of Liquid, Deliquescent or Unstable Drugs with Fusible Excipients in Hard Gelatin Capsules

The in vitro release profiles of four liquid or deliquescent model drugs incorporated in various Gelucire^R excipients were examined. In every case, it was possible to obtain release of the active substance as rapidly as with the equivalent commercial soft gelatine capsules tested. Gelucire^R grades with high HLB values (despite having high melting points) were found to be the most favorable. Release patterns could be related to the behaviour of the Gelucire^R bases in the gastric fluid

Drug-excipient ratio played a prominent role, which differed when hydrophilic or hydrophobic Gelucire^R types were used. Storage of the capsule formulations for more than two years did not usually change the drug release profiles significantly, but chloral hydrate capsules could not be stocked for more than a few months