Mayo Clinic and HealthyPlace.com offer lists of monoamine oxidase inhibitors, or MAOIs, on their websites. Food and Drug Administration-approved MAOIs include isocarboxazid, phenelzine, selegiline and tranylcypromine, as listed by Mayo Clinic.
MAOIs were the first antidepressant medications ever developed, according to Mayo Clinic. Due to side effects and safety concerns, doctors usually prescribe newer-generation antidepressants, but MAOIs are an effective option when other antidepressants fail. MAOIs treat depression by preventing monoamine oxidase from removing serotonin, norepinephrine and dopamine from the brain. Common side effects of MAOIs include dizziness or lightheadedness, dry mouth, insomnia, headache, and nausea, diarrhea or constipation. Other side effects include involuntary muscle jerks, reduced sexual desire, low blood pressure, weight gain and muscle aches.