Abstract
Quantitative structure-activity relationships (QSAR) relating biological activity to physiochemical descriptors have been successfully used for a number of years. It is also long recognized that pharmacokinetic parameters may play an important and even determinant role in drug action. This prompted several researchers to focus attention to pharmacokinetic parameters as potential descriptors in quantitative drug design. A number of examples of quantitative structure-pharmacokinetic relationships (QSPR) have appeared in the literature. The present contribution reviews some developments in this field. In particular, a number of concepts and problems are critically discussed, rather than compilations of examples already published in recent reviews. Attention will be paid to the main processes of the pharmacokinetic or toxicokinetic phase in drug action, including absorption, distribution and elimination (biotransformation and excretion). It is clear that quantitative approaches are of considerable interest to toxicologists, since these methods may contribute to the development of real predictive toxicology.