Serotonin reuptake inhibitor antidepressants, such as selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), and serotonin modulators with SSRI-like properties are pharmacotherapy options for major depressive and anxiety disorders. Inadequate response and treatment-related adverse events are known challenges in antidepressant therapy. Genetic variations in genes encoding the drug metabolizing enzymes, CYP2D6, CYP2C19 and CYP2B6, have been shown to alter antidepressant biotransformation, which may potentially affect dosing, efficacy, and tolerability. [from
PharmGKB]