isocarboxazid

Isocarboxazid

Isocarboxazid, sold under the brand name Marplan among others, is a non-selective irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class. Along with phenelzine and tranylcypromine, it is one of the three classic irreversible, non-selective MAOIs used as antidepressants in modern psychiatric practice. Availability varies by country; in the United States, all three remain available for clinical use, though isocarboxazid is prescribed less often than phenelzine or tranylcypromine. Its lower use has been attributed in part to practical issues of affordability and availability, a smaller literature base, and the absence of an FDA-approved generic equivalent. Isocarboxazid is used primarily in treatment-resistant depression. It has demonstrated efficacy in various depressive subtypes, including atypical depression, melancholic depression, and endogenous depression. Older studies also reported improvement in anxious depressive states, including nonpsychotic, nonmelancholic anxious depression and depressed patients with anxiety symptoms. The usual effective dose range is 30–60 mg/day, although expert clinicians have used doses up to 80 mg/day, with greater antidepressant effects as well as more side effects. It may also be considered as an alternative classic MAOI when phenelzine or tranylcypromine is not well tolerated, including when troublesome daytime somnolence, sedation, sleep disturbance, or other adverse effects limit treatment. Although there is less comparative research and clinical use than for phenelzine or tranylcypromine, contemporary MAOI expert gu...