Is pharmacovigilance still a clinical science?

Louis Lewin, better known for his popular works on poisons, wrote the first book on Side Effects of Drugs ("Nebenwirkungen der Arzneimitiel") in 1881. In the introduction to the 3rd edition (1899) he postulated: "As valuable as reports on side or after-effects of drugs per se may be, as much the practitioner may benefit from instructions as to how to avoid and treat such effects for his patients' sake, the true educational impulse results solely from demonstrating the link between such phenomena and other biological facts. Where purely chemical effects are believed to be causal they should, if possible, be elucidated." He knew what he was talking about, for he met with stiff resistance from some clinicians whose unthinking approach to drug therapy he openly criticized. While research on the mechanisms of therapeutic actions or interactions are today pursued vigorously by experimental and clinical pharmacologists, the pharmacological, biochemical and immunological causes of adverse reactions are much less commonly studied. We still do not know why the practolol syndrome occurred, and even frequent pulmonary reactions to such widely prescribed drugs as the ACE inhibitors still await clarification. Quite apart from the apparent lack of scientific interest in such matters, there is rarely regulatory action obliging the manufacturer to sponsor such studies; it is not surprising that the funds for such studies are not forthcoming. The differential diagnosis of an adverse drug event is not an administrative act but a recurrent medical problem, and one with which the general practitioner or the practising specialist are particularly likely to find themselves faced. Where faced with unusual symptomatology of a type falling outside his or her own discipline, the doctor can always seek the advice of a consultant in the field of medicine concerned. The possibility of finding a consultant with special knowledge of adverse effects as such is, however, much more limited; even in the most highly developed countries, specialists in adverse reaction studies are