Hirokazu Makita

Suitable Size of Preparations to Evaluate the Bioavailability of Enteric-Coated Preparations by the Use of Gastric-Acidity-Controlled Rabbits

The limiting size of enteric-coated preparations for which it is possible to evaluate the bioavailability by using gastric-acidity-controlled rabbits (GAC-rabbits) was investigated. Entericcoated preparations with different diameters were administered to GAC-rabbits, and drug bioavailability from each preparation was evaluated. In the case of enteric-coated granules, there was no problem in evaluating the bioavailability. However, in the case of enteric-coated tablets, the maximum size for which it was possible to evaluate the bioavailability was 4.1mm in diameter. The results indicate that the use of GAC-rabbits in bioavailability studies of enteric-coated preparations is restricted by the size of the preparations.