MAOIs (Monoamine Oxidase Inhibitors) Side Effects

MAOIs were the first class ofantidepressantsto be developed. They fell out of favor because of concerns about interactions with certain foods and numerousdrug interactions. MAOIs elevate the levels of norepinephrine, serotonin, anddopamine通过抑制一种叫做单胺氧化酶的酶。Monoamine oxidase breaks down norepinephrine, serotonin, and dopamine. When monoamine oxidase is inhibited, norepinephrine, serotonin, and dopamine are not broken down, increasing the concentration of all three neurotransmitters in the brain.

MAOIs also are used for the treatment ofParkinson'sdisease.

Since MAOIs work in the brain and affect neurotransmitters, they have many side effects. Side effects of MAOIs are:

• Sudden drop in官网地址bwinupon standing up (直立性低血压)
• Lack of strength
• Weakness
• Nausea
• Vomiting
• Dizziness
• Drowsiness
• Headache
• Fatigue
• Agitation
• Abnormal voluntary movement
• Dry mouth
• Abdominal pain
• Anxiety
• Change in mood or behavior
• Weight gain
• Impotence(erectile dysfunction,ED)

MAOIs也盒装战争nings ofsuicidalthinking andsuicidalbehavior in children, adolescents, and young adults.

MAO inhibitors should be avoided with other antidepressants such asparoxetinefluoxetine,amitriptyline,nortriptyline,bupropion;painmedications likemethadone,tramadol, andmeperidine; dextromethorphan, St. Johns Wort,cyclobenzaprine, andmirtazapine. Such combinations lead to high serotonin levels which may lead toconfusion,high blood pressure,tremor,hyperactivity,coma, and death. These medications should not be used within 14 days of stopping an MAOI.

MAOIs also interact withseizuremedications likecarbamazepine(TegretolTegretol XR,Equetro,Carbatrol)andoxcarbazepine(Trileptal) through unknown mechanisms, increasing side effects.

MAOIs are not recommended for use with medications like pseudoephedrine, phenylephrine,ephedrine, and phenylpropanolamine. The combination of MAO inhibitors and thesedrugscan cause an acute hypertensive episode.

Monoamine oxidase also breaks down tyramine, a chemical present in aged cheese, wines, and other aged foods. Since MAOIs inhibit monoamine oxidase, they decrease the breakdown of tyramine from ingested food, thus increasing the level of tyramine in the body. Excessive tyramine can elevate blood pressure and cause a hypertensive crisis. Patients treated with MAOIs should adhere to recommended dietary modifications that reduce the intake of tyramine.

Examples of oral MAOIs include:

1. rasagiline(Azilect),
2. selegiline(Eldepryl, Zelapar),
3. isocarboxazid (Marplan),
4. phenelzine (Nardil), and
5. tranylcypromine (Parnate).

Selegiline is also available in a topical patch form called Emsam.

• The FDA classifies MAO inhibitors inpregnancycategory C, which means that there is no established evidence of safe and effective use of MAO inhibitor inpregnantwomen. Therefore, infant risk cannot be ruled out.
• It is not known whether MAO inhibitors enterbreast milk; however, MAO inhibitors should be avoided innursingmothers to avoid harm to the fetus.