[Follow-up of antidepressive therapy in psychiatric clinical practice].

The therapeutic drug monitoring of antidepressant drugs is of interest to adapt dosage regimens to reduce the number of non-responder patients, to reduce drug side effects and to detect non-compliant patients. A therapeutic range is defined for many of these drugs and their linear or non-linear kinetics are important parameters in clinical practice to define the posology. Some patients, because of when there is drug biotransformation polymorphism, are exposed to drug accumulation a deficit in isoenzymes of cytochrome P450. The existence of these isoenzymes explains the possibility of non-linear kinetics and drug interactions.