Definition: A class of antidepressant drugs which block the activity of monoamine oxidase, an enzyme responsible for the breakdown of monoamines. Monoamines include the neurotransmitters serotonin, norepinephrine, and dopamine. Low levels of neurotransmitters are associated with depression. When these neurotransmitters can't be readily broken down, more becomes available and the patient's depression improves. Because monoamine oxidase inhibitors also block the breakdown of a monoamine called tyramine, foods and beverages containing tyramine must be avoided. High levels of tyramine in the body can lead to a life-threatening condition called a hypertensive reaction.
Also Known As: MAOIs
