(phenelzine sulfate)
NARDIL is a potent inhibitor of monoamine oxidase. Because this enzyme is widely distributed throughout the body, diverse pharmacologic effects can be expected to occur. When they occur, such effects tend to be mild or moderate in severity (see below), often subside as treatment continues, and can be minimized by adjusting dosage; rarely is it necessary to institute counteracting measures or to discontinue NARDIL.
Common side effects include:
Nervous System—Dizziness, headache, drowsiness, sleep disturbances (including insomnia and hypersomnia), fatigue, weakness, tremors, twitching, myoclonic movements, hyperreflexia.
Gastrointestinal—Constipation, dry mouth, gastrointestinal disturbances, elevated serum transaminases (without accompanying signs and symptoms).
Metabolic—Weight gain.
Cardiovascular—Postural hypotension, edema.
Genitourinary—Sexual disturbances, eg, anorgasmia and ejaculatory disturbances and impotence.
Less common mild to moderate side effects (some of which have been reported in a single patient or by a single physician) include:
Nervous System—Jitteriness, palilalia, euphoria, nystagmus, paresthesias.
Genitourinary—Urinary retention.
Metabolic—Hypernatremia.
Dermatologic—Pruritus, skin rash, sweating.
Special Senses—Blurred vision, glaucoma.
Although reported less frequently, and sometimes only once, additional severe side effects include:
Nervous System—Ataxia, shock-like coma, toxic delirium, manic reaction, convulsions, acute anxiety reaction, precipitation of schizophrenia, transient respiratory and cardiovascular depression following ECT.
Gastrointestinal—To date, fatal progressive necrotizing hepatocellular damage has been reported in very few patients. Reversible jaundice.
Hematologic—Leukopenia.
Immunologic—Lupus-like syndrome
Metabolic—Hypermetabolic syndrome (which may include, but is not limited to, hyperpyrexia, tachycardia, tachypnea, muscular rigidity, elevated CK levels, metabolic acidosis, hypoxia, coma and may resemble an overdose).
Respiratory—Edema of the glottis.
General—Fever associated with increased muscle tone.
Withdrawal may be associated with nausea, vomiting, and malaise.
An uncommon withdrawal syndrome following abrupt withdrawal of NARDIL has been infrequently reported. Signs and symptoms of this syndrome generally commence 24 to 72 hours after drug discontinuation and may range from vivid nightmares with agitation to frank psychosis and convulsions. This syndrome generally responds to reinstitution of low-dose NARDIL therapy followed by cautious downward titration and discontinuation.
Read the Medication Guide that comes with you or your family member's antidepressant medicine. This Medication Guide is only about the risk of suicidal thoughts and actions with antidepressant medicines. Talk to your, or your family member's, healthcare provider about:
What is the most important information I should know about antidepressant medicines, depression and other serious mental illnesses, and suicidal thoughts or actions?
How can I watch for and try to prevent suicidal thoughts and actions in myself or a family member?
Call a healthcare provider right away if you or your family member has any of the following symptoms, especially if they are new, worse, or worry you:
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
What else do I need to know about antidepressant medicines?
This Medication Guide has been approved by the U.S. Food and Drug Administration for all antidepressants.
October 2008
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