MAOIs - Monoamine Oxidase Inhibitors - TYRAMINE TOXICITY - Pharmacology

MAOI inhibits MAO which is present in gut, liver and neuron. MAO actually degrade any leaked out neurotransmitter in the neuron at rest. so this degradation is inhibited by MAOI. when the action potential arrives and there is release of neurotransmitter from synaptic vesicles, there is also release of those leaked out neurotransmitters into the synaptic cleft and cause more cellular response which leads to antidepressant effect. MAOI have washout time of 2 weeks before any other antidepressant is prescribed. MAOI have intense kind of food drug and drug drug interactions therefore there use is limited. Tyramine toxicity can lead to hypertensive crisis. other adverse effects are nausea, stroke, seizure. seligline, tranylcyproamine, phenalzine and isocarboxazid are included in MAOIs.