Use of antipsychotics in the treatment of depressive disorders

SUMMARY: There is a long history of using antipsychotic medications in the treatment of depressive disorders. Atypical antipsychotics, which have fewer side effects than traditional antipsychotics, have been used as monotherapy or adjunctively with antidepressants to treat depressive disorders with or without psychotic symptoms. The antidepressant effect of atypical antipsychotics involves regulation of monoamine, glutamate, gamma-aminobutyric acid (GABA), cortisol, and neurotrophic factors. To date, the United States Food and Drug Administration (USFDA) has approved aripiprazole and quetiapine slow-release tablets as adjunctive treatment for depressive disorders, and the combination of olanzapine and fluoxetine for the treatment of treatment-resistant depression. When using atypical antipsychotics in the treatment of depressed patients, clinicians need to monitor patients for the emergence of adverse effects including extrapyramidal symptoms (EPS), weight gain, and hyperglycemia.