[Drug therapy in the elderly. What should we know?].

Because of the increasing longevity of the population, a growing number of very old people are exposed to medications. Drug therapy in this population is difficult because of our lack of knowledge. The number of drugs administered is generally high and the prescription is often inappropriate. Changes in body composition, malnutrition and renal failure can cause drug accumulation and toxicity. However, hepatic metabolism via cytochrome P450 does not seem to be markedly influenced by oldness. Iatrogenic pathology is frequent in the elderly and may lead to hospitalisation and reduction in quality of life. Specific education of the medical care team should be promoted in order to tackle this important problem of public health.