isocarboxazid

drug

Also known as: marplan

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Last updated

June 29, 2026

Quick Summary

Isocarboxazid is an antidepressant drug used to relieve depression. It belongs to the class of monoamine oxidase inhibitors (MAOIs). MAOIs work by inhibiting an enzyme in the liver and brain that breaks down monoamine neurotransmitters, such as serotonin and norepinephrine. By preventing the breakdown of these neurotransmitters, MAOIs allow them to accumulate in the brain, which can help to alleviate symptoms of depression. Isocarboxazid was first used in 1959. MAOIs are typically prescribed when other antidepressants have not been effective.12

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antidepressant
For instance, the MAOIs—chiefly isocarboxazid, phenelzine, and tranylcypromine—in general are used only after treatment with tricyclic drugs has proved unsatisfactory, because these drugs’ side effects are unpredictable and their complex interactions are incompletely understood. Fluoxetine often relieves cases of depression that have failed to yield to tricyclics or MAOIs.
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For instance, the MAOIs—chiefly isocarboxazid, phenelzine, and tranylcypromine—in general are used only after treatment with tricyclic drugs has proved unsatisfactory, because these drugs’ side effects are unpredictable and their complex interactions are incompletely understood. Fluoxetine often relieves cases of depression that have failed to yield to tricyclics or MAOIs.
Read More