TPH2 activation may be considered a new prospective in the treatment of neuropsychiatric diseases related to brain 5-HT levels.[27] TPH2 gene variants are related to the efficacy of disulfiram treatment for cocaine addiction.[28] Because cocaine's mechanism of action involves blocking dopamine, norepinephrine, and serotonin transporters,[29] we also evaluated the role of a functional variant in TPH2. Here, TPH2 is linked to cocaine dependence.