Maoi types

Are structurally related to amphetamines and are orally active. The older, standard drugs inhibit both MAO-A (monoamine oxidase type A), which metabolizes NE, 5-HT, and tyramine, and MAO-B (monoamine oxidase type A), which metabolizes dopamine. Tranylcypromine is the fastest in onset of effect but has a shorter duration of action (about 1 week) than other MAOIs (2–3 weeks). In spite of these prolonged actions, the MAOIs are given daily. They are inhibitors of hepatic drug-metabolizing enzymes and cause drug interactions. Selegiline, a selective inhibitor of MAO type B, was recently approved for treatment of depression