The chapter on antidepressants discusses and reviews the use of tricyclic antidepressants, monoamine oxidase inhibitors, selective serotonin reuptake inhibitors, and serotonin-norepinephrine reuptake inhibitors, as well as bupropion, mirtazapine, nefazodone, trazodone, and the newer antidepressants vilazodone and vortioxetine. It reviews each medication’s mechanism of action, clinical characteristics, potential medication interactions, adverse effects, and other risks. The chapter also reviews emerging pharmacotherapies such as ketamine, esketamine, and brexanolone. It also briefly discusses complementary and alternative pharmacotherapies. The chapter includes an in-depth discussion of the clinical use of antidepressants for the treatment of unipolar depression and other psychiatric and medical disorders. It also discusses the use of antidepressants in women of childbearing age, notably in regards to pregnancy and breastfeeding considerations. Finally, each chapter includes a table of antidepressants that includes each medication’s generic and brand names, usual adult doses, pertinent clinical comments, black box warnings, and FDA indications.