Tranylcypromine is a non-hydrazine monoamine oxidase inhibitor belonging to the class of antidepressants called MAOIs. This drug is indicated in the treatment of major depression, dysthymic disorder, and atypical depression. It also is useful in panic and phobic disorders. The monoamine oxidase is an enzyme that catalyzes the oxidative deamination of many amines like serotonin, norepinephrine, epinephrine, and dopamine. There are 2 isoforms of this protein: A and B. The first one is found in cells located in the periphery and breakdown serotonin, norepinephrine, epinephrine, dopamine, and tyramine. The second one, the B isoform, breakdowns phenylethylamine, norepinephrine, epinephrine, dopamine, and tyramine. This isoform is found in the extracellular tissues and mostly in the brain. The mechanism of action of the MAOIs is still not determined, it is thought that they act by increasing free serotonin and norepinephrine concentrations and/or by altering the concentrations of other amines in the CNS. MAO A inhibition is thought to be more relevant to antidepressant activity than the inhibition caused by MAO B. Selective MAO B inhibitors have no antidepressant effects. An overdose of this drug will result in insomnia, restlessness, and anxiety. Hypotension, dizziness, weakness, and drowsiness may occur, progressing in severe cases to extreme dizziness and shock. This drug is administered as an oral tablet.

Tranylcypromine Amine Oxidase Serotonin Antidepressant Pathway References