The use of buccal partitioning as a model of drug absorption interactions.

Bioavailability describes both the rate and extent of drug absorption. The buccal absorption technique is a useful method for the examination of changed extent of drug absorption resulting from drug absorption interactions. The present work examined the usefulness of drug recovery profiles (after buccal absorption) in evaluating the rate of drug absorption. Recovery data, in the case of propranolol, did not change markedly after marked changes in the drug absorption rate, indicating that recovery profiles are a poor monitoring tool for changed absorption rates. The rate of drug absorption can be found using the buccal absorption method; however, this involves several different experiments on different days and, also, data must be found by measuring the drug in the absorption solution which also contains the interactant. The latter agent may interfere with drug assay procedures. The present work involved the model drug propranolol. Other drugs perhaps may behave differently.