Medications for Depression: Monoamine Enhancers and Esketamine (Antidepressants)

In this chapter, “drugs for depression,” the authors are covering the description of neuroscience-based nomenclature (NbN), pharmacological action, therapeutic effect, side effect, and drug-drug interaction, based on the conventional subgrouping of “antidepressant.” They include selective serotonin reuptake inhibitors (SSRIs), serotonin partial agonist/reuptake inhibitors (SPARIs), serotonin antagonist/reuptake inhibitor (SARI), serotonin-norepinephrine reuptake inhibitors (SNRIs), norepinephrine-dopamine reuptake inhibitor (NDRI), selective norepinephrine reuptake inhibitor (NRI), melatonin receptor agonist, noradrenergic and specific serotonergic antidepressant (NaSSA), serotonin reuptake enhancer (SRE), monoamine oxidase inhibitors (MAOIs), and tricyclic antidepressant/tetracyclic antidepressant (TCA/TeCA). Moreover, the novel drugs for depression (brexanolone, zuranolone, and mifepristone) or adjunctive treatments (olanzapine, quetiapine, aripiprazole, brexpiprazole, ketamine/esketamine) on top of existing SNRIs or SSRIs are also included. In addition, for the monoamine enhancers, the relationship between neurogenesis and antidepressant action has been described. Along with the conventional subgrouping of “antidepressant,” the potential influences of sex, race, and ethnicity on the antidepressant psychopharmacokinetics and pharmacodynamics are also comprehensively covered. Then, the symptom-based selection algorithm of drugs for depression has been introduced, based on neuroanatomical and neurochemical reductions for the symptoms of major depression. Finally, a pharmacological strategy algorithm for treatment-resistant major depression has been introduced. The algorithm includes optimization, switching, combination, and augmentation.