ABSTRACT
Many serious adverse efFects of drugs cannot be identified in the clinical trials required to demonstrate efficacy prior to marketing, either because they occur too rarely, or because there is too long a time delay between the initial use of the drug and the appearance of the adverse event. As a result, these adverse effects are first encountered in the uncontrolled world of everyday clinical practice. To detect and quantify these serious adverse effects, on the basis of information captured from everyday practice, is the task of drug safety postmarketing surveillance (PMS).
