Phenelzine elevates levels of GABA; this may contribute to its anxiolytic properties and superior efficacy with treatinganxiety. Because the enzyme is widely distributed throughout the body, diverse effects can be expected, but are mild to moderate, often subsiding as treatment continues.
It should be noted that Pfizer, the maker of Nardil, changed the formulation of Nardil in late 2003, removing many of the excipient ingredients (substances used to dilute), including the hard coating. It is possible that the current version of the drug is not being absorbed as well into the bloodstream due to being less protected from stomach acid. The indicated dosage was not altered by Pfizer, nor did they advise physicians or pharmacies of these changes, yet the recommended dose seems not to have the desired effect on many people taking it. Nardil’s original formulation is no longer available.
Monoamine oxidase is a complex enzyme system that is widely distributed in the body. Drugs to inhibit monoamine oxidase are linked to a number of clinical effects. It is therefore unknown whether MAO inhibition, other pharmacologic actions, or an interaction of both is responsible for the clinical effects seen. Because of this, the physician involved should become familiar with all the effects produced by these drugs.
Indications and Dosage:
Nardil is indicated for the treatment of bulimia, atypical depression, anxiety disorders, refractory depression, and social anxiety disorder (SAD; social phobia). The drug has shown effective in depression individuals clinically characterized as “atypical,” “nonendogenous,” or “neurotic.” These patients often exhibit a mix of anxiety and depression along with phobic or hypochondriacal features.
However, Nardil should rarely be the first antidepressant tried. It proves more suitable for use with people who have failed to respond to more common drugs associated with these conditions.
The initial dose of Nardil is normally one 15mg tablet three times a day. From there, dosage should increase to at least 60mg/day at a fairly accelerated pace, depending on the patient’s tolerance. It may be necessary to increase dosage up to 90mg/day for optimal MAO inhibition. Many people do not show any clinical response until at least 4 weeks of treatment at the 60mg/day level.
After one achieves the maximum benefit from Nardil, the dosage should be slowly reduced over a number of weeks. Maintenance dosage may be as low as one tablet, 15mg, a day or every other day, and should be continued for as long as needed.
The most common side effects of Nardil treatment include dizziness, headache, drowsiness, insomnia, hypersomnia, fatigue, weakness, myoclonic movements, hyperrefexia, tremors, twitching, dry mouth, gastrointestinal disturbances, constipation, weight gain, edema, postural hypotension, and sexual disturbances such as anorgasmia and delayed ejaculation in men.
Rarer side effects, mostly mild to moderate in severity, include jitteriness, euphoria, paresthesias, palilalia, nystagmus, urinary retention, blurred vision, pruritus, skin rash, sweating, glaucoma, and hypernatremia.
There have been serious side effects reported, though less frequently, and sometimes only once. These include ataxia, shock-like coma, toxic delirium, manic reaction, acute anxiety reaction, precipitation of schizophrenia, transient respiratory and cardiovascular depression following ECT, convulsions, reversible jaundice, leucopenia, lupus-like syndrome, fever associated with increased muscle tone, edema of the glottis, muscular rigidity, metabolic acidosis, hypoxia, coma possibly resembling overdose, tachycardia, hyperpyrexia, and tachypnea.
In patients receiving nonselective MAOI treatment along with serotoninergic agents, reports of serious, sometimes fatal reactions have been reported. Because phenelzine is an MAOI, it should not be used concomitantly with a serotoninergic agent, such as fluoxetine, paroxetine, velafexine, etc.
Foods that should be avoided for patients taking Nardil include aged cheeses, yogurt, sour cream, beef or chicken liver, tenderized meats, avocadoes, bananas, red wine and other distilled spirits, chocolate, ginseng, fava beans, soy sauce, raisins, figs, caffeine, and beer. Foods containing high levels of tyramine should be avoided as well. Examples of tyramine-containing foods include leftovers that have been in the refrigerator more than 24-48 hours, sauerkraut, salami, dried, fermented, salted, smoke or pickled meats – especially pepperoni and liverwurst, all types of nuts, mincemeat pie.
Information for Parents and Kids:
Nardil is not recommended for children, since the safety and efficacy of the drug for children under age 16 have not been determined. In clinical studies, antidepressants increased risks of suicidality in thought and behavior in children and teenagers with depressive symptoms or other psychiatric disorders. Anyone considering using Nardil or any other antidepressant in a child or adolescent must balance the risk with the clinical need, but Nardil is not approved for treating children.
Warnings and Precautions:
Individuals taking Nardil should watch for any change in symptoms or any new ones that crop up suddenly, especially agitation, hostility, panic, hyperactivity, anxiety, restlessness, and suicidal behavior or thoughts, and report them to a doctor immediately. It’s very important to be especially observant in the beginning stages of treatment and whenever there is a change in dosage.
Food and drug limitations for MAOIs must be followed; failure to do so may lead to potentially fatal side effects. While taking phenelzine, the appearance of a headache or any other unusual symptoms should be reported to your physician promptly.
Diabetics should be prescribed Nardil under caution, since it is as yet unclear how MAOIs affect blood sugar levels. Consult your doctor before any elective surgery if you are taking Nardil.
Nardil use should not be ceased abruptly, or you may experience withdrawal symptoms.
Withdrawal symptoms associated with Nardil include nightmares, strange behavior, convulsions, malaise, nausea, vomiting and agitation.
Over-dosage & Contraindications:
Overdose, whether accidental or intentional, may be more common in depressed individuals.
Depending on the amount of overdosage, symptoms may be varying and mixed, including signs and symptoms of central nervous system and cardiovascular stimulation and/or depression. Signs or symptoms may be minimal or altogether absent during the initial 12 hour period following ingestion and may develop slowly thereafter, reaching a maximum in 24-48 hours. There have been reports of death following overdose of Nardil. Therefore immediate hospitalization with observation and monitoring is vital.
Some of the signs and symptoms of overdose may include (alone or in combination) drowsiness, faintness, dizziness, hyperactivity, agitation, irritability, severe headache, hallucinations, trusmus, opisthotonus, rigidity, convulsions, coma, rapid and irregular pulse, hypertension, hypotension, vascular collapse, precordial pain, respiratory depression and failure, hyperpyrexia, diaphoresis, and clammy skin.
Nardil should not be used by persons hypersensitive to the drug or its ingredients, those with pheochromocytoma, congestive heart failure, liver disease or a history of liver disease, or individuals with abnormal liver function.
The drug should not be used in combination with dextromethorphan or with CNS depressants such as alcohol and certain narcotics. In persons undergoing MAOI therapy who have been given a single dose of meperidine, there have been reports of hyperpyrexia, circulatory collapse, excitation, seizures, delirium, coma, and death. Nardil should not be used together with or in rapid succession to other MAOIs due to the risk of hypertensive crises and convulsive seizures, profuse sweating, tremor, delirium, excitation, coma and circulatory collapse.
Generic Name: phenelzine
Chemical Formula: C8H12N2
Routes of Administration: oral
Elimination Half Life: approximately 1.2 hours
Legal Status: by prescription only