The contribution of epidemiology to the study of drugs.

Epidemiology is concerned with the distribution of disease and health in human populations. Drugs are one of the factors that influence such a distribution. Pharmacoepidemiology can be defined as the application of epidemiologic knowledge, methods, and reasoning to the study of the effects (beneficial and adverse) and uses of drugs in human populations. Pharmacoepidemiology aims to describe, explain, control, and predict the effects and uses of pharmacologic treatment modalities in a defined time, space, and population. The present article is an introduction to the contributions of epidemiology to the study of drugs.