No

Antidepressant, Monoamine Oxidase Inhibitor

Symptomatic treatment of atypical, nonendogenous, or neurotic depression

C

Hypersensitivity to phenelzine; uncontrolled hypertension; pheochromocytoma; hepatic disease; congestive heart failure; concurrent use of sympathomimetics (and related compounds), CNS depressants, ethanol, meperidine, bupropion, buspirone, guanethidine, serotonergic drugs (including SSRIs) - do not use within 5 weeks of fluoxetine discontinuation or 2 weeks of other antidepressant discontinuation; general anesthesia, local vasoconstrictors; spinal anesthesia (hypotension may be exaggerated). Foods with a high content of tyramine, tryptophan, or dopamine, chocolate, or caffeine.

Safety in children <16 years of age has not been established; use with caution in patients who are hyperactive, hyperexcitable, or who have glaucoma, hyperthyroidism, suicidal tendencies, or diabetes; avoid use of meperidine within 2 weeks of phenelzine use. Hypertensive crisis may occur with tyramine, tryptophan, or dopamine-containing foods. Should not be used in combination with other antidepressants. Hypotensive effects of antihypertensives (beta-blockers, thiazides) may be exaggerated. Use with caution in depressed patients at risk of suicide. May cause orthostatic hypotension - use with caution in patients with hypotension or patients who would not tolerate transient hypotensive episodes (cardiovascular or cerebrovascular disease) - effects may be additive with other agents which cause orthostasis. Has been associated with activation of hypomania and/or mania in bipolar patients. May worsen psychotic symptoms in some patients. Use with caution in patients at risk of seizures, or in patients receiving other drugs which may lower seizure threshold. Toxic reactions have occurred with dextromethorphan. Discontinue at least 48 hours prior to myelography.

Cardiovascular: Orthostatic hypotension, edema

Central nervous system: Dizziness, headache, drowsiness, sleep disturbances, fatigue, hyper-reflexia, twitching, ataxia, mania

Dermatologic: Rash, pruritus

Endocrine & metabolic: Decreased sexual ability (anorgasmia, ejaculatory disturbances, impotence), hypernatremia, hypermetabolic syndrome

Gastrointestinal: Xerostomia, constipation, weight gain

Genitourinary: Urinary retention

Hematologic: Leukopenia

Hepatic: Hepatitis

Neuromuscular & skeletal: Weakness, tremor, myoclonus

Ocular: Blurred vision, glaucoma

Miscellaneous: Diaphoresis

Symptoms of overdose include tachycardia, palpitations, muscle twitching, seizures, insomnia, restlessness, transient hypertension, hypotension, drowsiness, hyperpyrexia, coma

Competent supportive care is the most important treatment for an overdose with a monoamine oxidase (MAO) inhibitor. Both hypertension or hypotension can occur with intoxication. Hypotension may respond to I.V. fluids or vasopressors and hypertension usually responds to an alpha-adrenergic blocker. While treating the hypertension, care is warranted to avoid sudden drops in blood pressure, since this may worsen the MAO inhibitor toxicity. Muscle irritability and seizures often respond to diazepam, while hyperthermia is best treated with antipyretics and cooling blankets. Cardiac arrhythmias are best treated with phenytoin or procainamide.

In general, the combined use of phenelzine with TCAs, venlafaxine, trazodone, and SSRIs should be avoided due to the potential for severe adverse reactions (serotonin syndrome, death)

MAOIs may inhibit the metabolism of barbiturates and prolong their effect

MAOIs in combination with dexfenfluramine, sibutramine, meperidine, fenfluramine, and dextromethorphan may cause serotonin syndrome; these combinations are best avoided

MAOIs in combination with amphetamines, other stimulants (methylphenidate), metaraminol, and decongestants (pseudoephedrine) may result in severe hypertensive reaction; these combinations are best avoided

Foods (eg, cheese) and beverages (eg, ethanol) containing tyramine, should be avoided in patients receiving an MAOI; hypertensive crisis may result

MAOIs inhibit the antihypertensive response to guanadrel or guanethidine; use an alternative antihypertensive agent

MAOIs in combination with levodopa and reserpine may result in hypertensive reactions; monitor

MAOIs in combination with lithium have resulted in malignant hyperpyrexia; this combination is best avoided

MAOIs may increase the pressor response of norepinephrine; monitor

MAOIs may prolong the muscle relaxation produced by succinylcholine via decreased plasma pseudocholinesterase

Tramadol may increase the risk of seizures and serotonin syndrome in patients receiving an MAOI

MAOIs may produce hypoglycemia in patients with diabetes; monitor

MAOIs may produce delirium in patients receiving disulfiram; monitor

Protect from light

Thought to act by increasing endogenous concentrations of norepinephrine, dopamine, and serotonin through inhibition of the enzyme (monoamine oxidase) responsible for the breakdown of these neurotransmitters

Onset of action: Within 2-4 weeks

Absorption: Oral: Well absorbed

Duration: May continue to have a therapeutic effect and interactions 2 weeks after discontinuing therapy

Elimination: In urine primarily as metabolites and unchanged drug

Oral:

Elderly: Initial: 7.5 mg/day; increase by 7.5-15 mg/day every 3-4 days as tolerated; usual therapeutic dose: 15-60 mg/day in 3-4 divided doses

Alcohol: Additive CNS effect, avoid use

Food: Avoid tyramine-containing foods

Blood pressure, heart rate, diet, weight, mood (if depressive symptoms)

glucose

Attempts should be made to avoid use of vasoconstrictor due to possibility of hypertensive episodes with monoamine oxidase inhibitors

Orthostatic hypotension in >10% of patients; meperidine should be avoided as an analgesic due to toxic reactions with MAO inhibitors

Take exactly as directed (do not increase dose or frequency); may take 2-3 weeks to achieve desired results; may cause physical and/or psychological dependence. Avoid excessive alcohol, caffeine, and other prescription or OTC medications not approved by prescriber. Avoid tyramine-containing foods (eg, pickles, aged cheese, wine). Maintain adequate hydration (2-3 L/day of fluids unless instructed to restrict fluid intake). You may experience postural hypotension (use caution when climbing stairs or changing position from lying or sitting to standing); drowsiness, lightheadedness, dizziness (use caution when driving or engaging in tasks requiring alertness until response to drug is known); anorexia, dry mouth (small frequent meals, frequent mouth care, chewing gum, or sucking lozenges may help); constipation (increased exercise, fluids, or dietary fruit and fiber may help); or diarrhea (buttermilk, yogurt, or boiled milk may help). Diabetic patients should monitor serum glucose closely (Nardil® may effect glucose levels). Report persistent insomnia; chest pain, palpitations, irregular or rapid heartbeat, or swelling of extremities; muscle cramping, tremors, or altered gait; blurred vision or eye pain; yellowing of eyes or skin; pale stools/dark urine; or worsening of condition. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to be pregnant. Breast-feeding is not recommended.

Watch for postural hypotension; monitor blood pressure carefully, especially at therapy onset or if other CNS drugs or cardiovascular drugs are added; check for dietary and drug restriction

Tablet, as sulfate: 15 mg

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Erich JL, Shih RD, and O'Connor RE, "'Ping-Pong' Gaze in Severe Monoamine Oxidase Inhibitor Toxicity," J Emerg Med, 1995, 13(5):653-5.

Georgotas A, Friedman E, McCarthy M, et al, "Resistant Geriatric Depression and Therapeutic Response to Monoamine-Oxidase Inhibitors," Biol Psychiatry, 1983, 18:195-205.

Goff DC and Jenike MA, "Treatment-Resistant Depression in the Elderly," J Am Geriatr Soc, 1986, 34(1):63-70.

Jenike MA, "MAO Inhibitors as Treatment for Depressed Patients With Primary Degenerative Dementia (Alzheimer's Disease)," Am J Psychiatry, 1985, 142:763.

Kaplan RF, Feinglass NG, Webster W, et al, "Phenelzine Overdose Treated With Dantrolene Sodium," JAMA, 1986, 255(5):642-4.

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Verrilli MR, Salanga VD, Kozachuk WE, et al, "Phenelzine Toxicity Responsive to Dantrolene," Neurology, 1987, 37(5):865-7.