What model for pharmacokinetic analysis of tissue distribution and bioequivalence

Pharmacokinetic analysis of experimental data is usually carried out through two different approaches: non compartmental model or standard compartmental models. Benefits and restrictions of these two approaches are here discussed, with attention to the studies of clinical pharmacokinetics and, particularly, to those of bioavailability and bioequivalence. In fact, different opinions about the most appropriate model to be used with these studies were encountered. Besides, the paper deals with European and American guidelines, data from a check of the literature published during 1995 on two international journals of clinical pharmacology and results of non-compartmental and non-linear fitting analyses on plasma concentrations obtained with an oral administration of a delayed dosage form in humans.