Abstract
6-Mercaptopurine (6-MP) polymorphs were administered to rabbits as intravenous injection, oral aqueous solution, oral hard capsule and effervescent capsule. When the form III powder was given in hard capsules, the dissolution from the capsule was very slow and the plasma levels after oral administration were also lower than those obtained with form I. On the other hand, the form III effervescent capsule prepared to enhance the dissolution gave an extent of bioavailability (EBA) about 1.5 times greater than that of form I. The time course data after oral administration of each dosage form were analyzed by means of the compartment model method and the statistical moment method. It appears that the difference of EBA after oral administration as the capsule dosage forms was chiefly attributable to the difference of apparent absorption rate. These results could be explained in terms of the differences of the mean disintegration and dissolution time (MDDT) obtained by means of the moment method.
