[The safety of drugs].

Pharmacological investigation provides drugs which are progressively more active, the therapeutic effect of which is inseparably bound to the possibility of provoking adverse effects. At the present time, drug safety can be evaluated at three levels: animal experiments, clinical studies and post marketing surveillance. A new drug is admitted in view of the results obtained through-out its development both in preclinical and clinical studies, when the benefits obtained are superior to the risks, in case of a particular disease, and based on the information available at that moment. Postmarketing surveillance permits the identification and quantification of adverse effects caused by commercialized drugs. Keeping in mind that drug safety is never absolute, everybody including physicians, government administration, and pharmaceutical industries, should be motivated in order to obtain efficacious and safe drugs in a climate of strictness, dialogue and realism.