For depression, selective serotonin reuptake inhibitors or serotonin- norepinephrine reuptake inhibitors are usually the mainstay of therapy. However, Axis 2 conditions (ie, obsessive-compulsive disorder) in a depressed patient might influence the choice of fluvoxamine over another agent. If the patient has an anxiety or substance abuse component in his or her Axis 2, perhaps an atypical antipsychotic such as quetiapine may be used. In teenagers with depression, clinicians should avoid a selective serotonin reuptake inhibitor or serotonin-norepinephrine reuptake inhibitor due to the "black box" warning related to enhanced suicidality. Treatment-resistant depression may require combinations of agents.