From the Guidelines
Monoamine Oxidase Inhibitors (MAOIs) can cause several significant side effects, including hypertensive crisis, orthostatic hypotension, insomnia, sexual dysfunction, weight gain, and edema, which require careful management and patient education. According to the clinical practice guideline for the assessment and treatment of children and adolescents with anxiety disorders 1, MAOIs play a role in most cases of serotonin syndrome and should be avoided in combination with any other serotonergic drug. The potential side effects of MAOIs can be managed through:
- Strict adherence to a low-tyramine diet to prevent hypertensive crisis
- Rising slowly and maintaining hydration to manage orthostatic hypotension
- Morning dosing to address insomnia
- Dose adjustment to manage sexual dysfunction
- Monitoring for weight gain and edema
- Avoiding combination with other serotonergic medications, such as SSRIs, to prevent serotonin syndrome, and allowing at least a 2-week washout period when switching between these drug classes. Some specific MAOIs and their dosages include:
- Phenelzine (45-90 mg daily)
- Tranylcypromine (20-60 mg daily)
- Selegiline transdermal patch (6-12 mg/24 hours), which generally causes fewer dietary restrictions at lower doses. Due to the risks associated with MAOIs, they are typically reserved for treatment-resistant depression after other options have failed, and patients must be thoroughly educated about medication interactions and dietary restrictions 1.
From the FDA Drug Label
In patients with bipolar disorder, treating a depressive episode with tranylcypromine tablets or another antidepressant may precipitate a mixed/manic episode. Hypotension, including postural hypotension, has been observed during therapy with tranylcypromine tablets. 5.8 Discontinuation Syndrome Abrupt discontinuation or dosage reduction of tranylcypromine tablets has been associated with the appearance of new symptoms that include dizziness, nausea, headache, irritability, insomnia, diarrhea, anxiety, fatigue, abnormal dreams, and hyperhidrosis. 5.9 Risk of Clinically Significant Adverse Reactions due to Persistence of MAO Inhibition after Discontinuation Although excretion of tranylcypromine tablets are rapid, inhibition of MAO may persist up to 10 days following discontinuation 5.10 Hepatotoxicity Hepatitis and elevated aminotransferases have been reported in association with tranylcypromine tablets administration. 5.11 Seizures Seizures have been reported with tranylcypromine tablets withdrawal after abuse, and with overdose. 5.12 Hypoglycemia in Diabetic Patients Some MAOIs have contributed to hypoglycemic episodes in diabetic patients receiving insulin or other blood-glucose-lowering agents. 5.13 Aggravation of Coexisting Symptoms of Depression Tranylcypromine tablets may aggravate coexisting symptoms in depression, such as anxiety and agitation. 5.14 Adverse Effects on the Ability to Drive and Operate Machinery Some tranylcypromine tablets adverse reactions (e.g., hypotension, faintness, drowsiness, confusion, disorientation) can impair a patient's ability to operate machinery or use an automobile.
The potential side effects of Monoamine Oxidase Inhibitors (MAOIs) such as tranylcypromine include:
- Hypotension and postural hypotension
- Activation of mania or hypomania in patients with bipolar disorder
- Discontinuation syndrome with symptoms such as dizziness, nausea, and headache
- Hepatotoxicity with hepatitis and elevated aminotransferases
- Seizures with withdrawal after abuse or overdose
- Hypoglycemia in diabetic patients
- Aggravation of coexisting symptoms of depression such as anxiety and agitation
- Adverse effects on the ability to drive and operate machinery due to hypotension, faintness, drowsiness, confusion, and disorientation. These side effects can be managed by:
- Monitoring patients for symptoms of hypotension and postural hypotension
- Screening patients for bipolar disorder before initiating treatment
- Gradually reducing the dose when discontinuing treatment
- Monitoring liver function and adjusting the dose as needed
- Avoiding the use of contraindicated medications
- Educating patients on the risks of hypoglycemia and the importance of monitoring blood glucose levels
- Counseling patients on the potential for aggravation of coexisting symptoms of depression
- Advising patients to avoid operating hazardous machinery or automobiles until they are reasonably certain that tranylcypromine therapy does not impair their ability to engage in such activities 2.
From the Research
Potential Side Effects of MAOIs
- Hypertensive crisis due to tyramine intake, commonly known as the "cheese effect" 3, 4, 5, 6
- Interaction with certain foods, such as aged cheeses and meats, which can cause life-threatening blood pressure elevations 3, 4, 5
- Adverse reactions with sympathomimetic and serotonergic drugs, including over-the-counter medications and illicit drugs like ecstasy (MDMA) 3, 7
- Risk of serotonin toxicity when combined with certain medications, such as dextromethorphan, chlorpheniramine, and brompheniramine 3, 7
- Myocardial injury and troponin release due to hypertensive crisis secondary to excessive tyramine intake 6
Management of MAOI Side Effects
- Patient education on avoiding certain foods and medications that can interact with MAOIs 3, 7
- Close monitoring of blood pressure and cardiovascular health 6
- Avoidance of over-the-counter medications and illicit drugs that can interact with MAOIs 3, 7
- Use of reversible and selective MAO-A inhibitors, which may reduce the risk of hypertensive crisis 4, 5
- Co-administration of tricyclic antidepressants with MAOIs, which may also reduce the risk of hypertensive crisis 4, 5