MAOI Drugs Guide

SimpleNursing Editorial Team Mar 12, 2023
patient receiving maoi drugs

Jump to Sections

  1. What are MAO Inhibitors (MAOIs)?
  2. Mechanism of Action of MAOIs
  3. MAOIs & Hypertensive Crisis Nursing Interventions
  4. Why are MAOIs considered a last-resort antidepressant?

Treating patients with depression typically involves medication therapy, including Monoamine oxidase inhibitors (MAOI) drugs.

MAOIs are typically reserved as a last resort treatment for depression when other medications have been ineffective or have caused intolerable side effects. They’re prescribed for individuals with treatment-resistant depression – meaning that other medications have not been effective in managing their symptoms.

As a nurse, you need to know about MAOIs for depression treatment and complications like a hypertensive crisis.

What are MAO Inhibitors (MAOIs)?

MAOIs are very powerful antidepressants used for depression, panic disorder, and social phobias. They’re typically used as a second-line treatment for depression when other medications have been ineffective or have caused intolerable side effects. 

Nurses may administer the medication as prescribed by the patient’s health care provider. It’s important to monitor patients taking MAOIs closely for side effects, including changes in blood pressure, heart rate, and mood. 

Patients taking MAOIs may need to follow a specific diet that avoids foods containing tyramine, as consuming tyramine-rich foods can lead to a dangerous increase in blood pressure.

Nurses should also educate patients taking MAOIs about the potential side effects of the medication, the importance of following dietary restrictions, and the need to avoid certain medications or supplements that can interact with MAOIs. 

List of MAOIs

  • Phenelzine functions as both an inhibitor and substrate of monoamine oxidase, leading to increased levels of catecholamines and serotonin within the brain. 
  • Selegiline works by elevating the amount of dopamine, a neurotransmitter that plays a crucial role in controlling movement.
  • Isocarboxazid permanently blocks the action of monoamine oxidases (MAOs) in the nervous system. 
  • Tranylcypromine nonselectively and irreversibly inhibits monoamine oxidase (MAO).

Mechanism of Action of MAOIs

MAOIs increase the availability of norepinephrine, serotonin, and dopamine in the brain. They work by inhibiting the activity of an enzyme called monoamine oxidase, which breaks down certain neurotransmitters such as serotonin, norepinephrine, and dopamine.

MAOI Contraindications

Patients taking MAOIs should avoid taking certain medications such as Tramadol, Meperidine, Dextromethorphan, and Methadone as they may increase the risk of developing serotonin syndrome. 

Additionally, it’s generally advised that SSRIs, SNRIs, TCAs, Bupropion, Mirtazapine, St. John’s Wort, and sympathomimetic amines (including stimulants), should be avoided when taking MAOIs due to potential interactions that can lead to adverse effects.

MAOIs & Hypertensive Crisis Nursing Interventions

MAOIs can cause a hypertensive crisis when taken with certain foods, medications, or substances that contain tyramine. Tyramine can cause the release of norepinephrine in the brain. 

When this happens, it can lead to a sudden and dangerous increase in blood pressure, which can cause symptoms such as severe headache, nausea, vomiting, sweating, and palpitations. In some cases, a hypertensive crisis can lead to a stroke or heart attack.

If a patient does experience a hypertensive crisis while taking MAOIs, nurses should follow these interventions:

  • Notify the healthcare provider. Notify the patient’s healthcare provider immediately so that they can evaluate the patient’s condition and provide appropriate treatment.
  • Monitor vital signs. Monitor the patient’s blood pressure, heart rate, and oxygen saturation to assess their condition and response to treatment.
  • Administer medication. Medication may sometimes be needed to lower the patient’s blood pressure. Nurses should administer medication as prescribed by the healthcare provider.
  • Provide supportive care. Nurses should provide supportive care to the patient, including administering oxygen, monitoring their fluid intake, and providing emotional support to help manage any anxiety or distress.

Why are MAOIs considered a last-resort antidepressant?

MAOIs are considered a last resort antidepressant to healthcare professionals for several reasons:

  • Side effects: MAOIs can cause various side effects, including dry mouth, dizziness, sleep disturbances, weight gain, and sexual dysfunction. Additionally, MAOIs can interact with a wide range of foods, medications, and substances, leading to potentially serious adverse effects.
  • Safety concerns: MAOIs can cause dangerous increases in blood pressure when taken with certain foods, medications, and substances. This can lead to stroke, heart attack, or other serious medical conditions.
  • The complexity of use: MAOIs require careful monitoring and follow-up by healthcare providers, and patients taking MAOIs must follow a specific diet and avoid certain foods and substances to prevent interactions. This can make MAOIs more difficult to prescribe and manage than other antidepressant medications.
  • The availability of other options: There are many other antidepressant medications available that are generally considered safer and easier to use than MAOIs. These medications include selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and atypical antidepressants.

Learn More Pharmacology in Less Time

MAOIs are one of many types of antidepressants, which is a small part of the pharmacology field. Overall, it’s a lot to take in, soaking up lots of time in studying.

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