Theoretical Models for Analysis of Synergy and Antagonism of Drugs

Abstract

The review presents the following methods of quantitative analysis of drug interactions: the Loewe additivity model, Bliss independence model, Webb's fractional pro­ducts method and the Chou model.

Therapeutic synergy is achieved by combining drugs to obtain higher benefits which could not be reached with individual drugs. The synergy improves not only the drug effect, but also leads to a dosage decrease at equal or increased efficacy and finally to reduction or delay of drug resistance as well as reduction of toxic effects. In some cases also a small improvement of drug effects without increasing adverse actions means a great clinical shift even without synergy.