THE REGULATORY VIEW ON DRUG-DRUG INTERACTIONS

Nowadays the majority of patients receive more than one drug simultane ously. Since drug-drug interactions and side-effects increase in a non linear fashion with the number of drugs administered, a drug, which mi ght interact with a commonly used comedication should be tested specif ically and systematically in this regard before marketing. So far no r egulatory framework precisely defines the requirements and the design of particular drug interaction studies. The directions and guidelines of the European Community contain only general outlines about preferre d study designs and the necessity of drug interaction studies. Valuabl e information can be found in the Guideline Special Population of the International Conference on Harmonization (ICH). On the other hand, th e general character of existing regulations enables the researcher to apply the most suitable approach to uncover therapeutically relevant i nteractions of a new drug before marketing. After marketing approval p ostmarketing surveillance is necessary to detect further drug interact ions of clincal relevance.