Pharamacogenetics and antidepressant treatment in integrative psychiatry perspective.

The concept of individualized drug therapy on the basis of pharmacogenetics has become a central focus in the treatment of depression. There is an increasing agreement about the importance of polymorphisms in cytochrome P450 enzymes and the effects of drug-drug interactions in relation to the incidence of adverse effects. There has been also increasing focus on the role of the drug transporter P-glycoprotein (P-gp) with regard to drug penetration into the brain. P-gp at the blood-brain barrier can exert a profound effect on the ability of some antidepressants to enter the brain. In addition, genetic polymorphism of the serotonin transporter has been investigated in relationship to the therapeutic response to several antidepressants, especially SSRIs. However, prediction of response on the basis of variants of candidate genes is incipient and remains elusive.