MAOI stands for monamine or monoamine oxidase inhibitors, a category of drugs that ameliorates depression by inhibiting the monoamine oxidase enzyme from metabolizing neurotransmitters or chemical messengers within the nervous system. This class of drugs is basically a drug of last resort when other antidepressants are not working for a patient. This is due to the fact that MAOIs have many side effects and produce severe interaction effects with certain medications. Additionally, a restricted diet is necessary when taking MAOIs because this group produces adverse reactions when taken with a variety of foods.
Marplan and Parnate
The Mayo Clinic states that four MAOI antidepressant drugs have been approved by the Food and Drug Administration. Two of these drugs are Marplan and Parnate. Both medications are prescribed specifically to treat depressive disorders after a failed therapy attempt; that is, after a patient did not respond well from treatment by another antidepressant. Marplan is to be used as a short-term medication with the restriction of use specified to be up to six weeks. Again, these antidepressants are not frequently prescribed because of their potential for serious adverse reactions.
Nardil is another monoamine oxidase inhibitor that is used to treat depression only after drug therapy with another medication has proved unsuccessful. Nardil can be used to treat anxiety or depression mixed with features of a phobic disorder.
Selegiline or Emsam is unique because it is the first antidepressant to be delivered by a skin or transdermal patch that delivers medication over a 24-hour period. The Mayo Clinic indicates that this medication provides a way to be free of the traditional strict dietary regimen when used in low milligram doses, yet dietary restrictions are needed for higher doses. Emsam is unique because of its therapeutic effects on individuals with Parkinson's disease: It improves motor function and acts as an immuno-stimulant, which appears to improve cognitive function in Parkinson's patients.