[Prediction of therapeutic response in depressive states]

Predicting the clinical improvement of patients with antidepressant drugs, at an early stage and in a individualistic manner, allows to choose the product which is most adapted to each case and to avoid leaving patients under an inefficient medication for several weeks. Predictability studies have multiplied. A general review of these studies is made here by examining the clinical, biological, electrophysiological, and finally the pharmacokinetic predictors. Clinical predictors have a practical use as they define certain clinical types of depression which best respond to antidepressants specific to a monoaminergic axis. It has been shown that a complete absence of symptomatic improvement after two weeks of treatment predicts the inefficacy of the treatment. Inversely, to this day, none of the biological predictors lead to a practical application during the treatment of patients, but they allow a better understanding of the antidepressants' mode of action. Finally, the elaboration of pharmacokinetic equations define for each patient the doses that allow to determine the therapeutic zones when these have been recognized.