Phenelzine sulfate is a hydrazine derivative. It has a molecular weight of 234.27 and is
chemically described as C8 H12 N2 • H2SO4. Its chemical structure is shown below:
Each NARDIL film-coated tablet for oral administration contains phenelzine sulfate
equivalent to 15 mg of phenelzine base and the following inactive ingredients: mannitol,
USP; corn starch, NF; croscarmellose sodium, NF; povidone, USP; edetate disodium,
USP; magnesium stearate, NF; isopropyl alcohol, USP; purified water, USP; opadry
orange Y30-13242A; simethicone emulsion, USP.
Monoamine oxidase is a complex enzyme system, widely distributed throughout the
body. Drugs that inhibit monoamine oxidase in the laboratory are associated with a
number of clinical effects. Thus, it is unknown whether MAO inhibition per se, other
pharmacologic actions, or an interaction of both is responsible for the clinical effects
observed. Therefore, the physician should become familiar with all the effects produced
by drugs of this class.
Pharmacokinetics
Absorption – Following a single 30 mg dose of NARDIL® (2 X 15 mg tablets), a
mean peak phenelzine plasma concentration (Cmax) of 19.8 ng/mL occurred at a time
(Tmax) of 43 minutes postdose.
Metabolism – NARDIL® is extensively metabolized, primarily by oxidation via
monoamine oxidase. After oral administration of 13C6-phenelzine, 73% of the
administered dose was recovered in urine as phenylacetic acid and
parahydroxyphenylacetic acid within 96 hours. Acetylation to N2-acetylphenelzine is a
minor pathway.
Elimination – The mean elimination half-life after a single 30mg dose is 11.6 hours.
Multiple dose pharmacokinetics have not been studied in man.
NARDIL has been found to be effective in depressed patients clinically characterized as
“atypical,” “nonendogenous,” or “neurotic.” These patients often have mixed anxiety and
depression and phobic or hypochondriacal features. There is less conclusive evidence of
its usefulness with severely depressed patients with endogenous features.
NARDIL should rarely be the first antidepressant drug used. Rather, it is more suitable
for use with patients who have failed to respond to the drugs more commonly used for
these conditions.
CONTRAINDICATIONS
NARDIL should not be used in patients who are hypersensitive to the drug or its
ingredients, with pheochromocytoma, congestive heart failure, a history of liver disease,
or abnormal liver function tests.
The potentiation of sympathomimetic substances and related compounds by MAO
inhibitors may result in hypertensive crises (see WARNINGS). Therefore, patients being
treated with NARDIL should not take sympathomimetic drugs (including amphetamines,
cocaine, methylphenidate, dopamine, epinephrine, and norepinephrine) or related
compounds (including methyldopa, L-dopa, L-tryptophan, L-tyrosine, and
phenylalanine). Hypertensive crises during NARDIL therapy may also be caused by the
ingestion of foods with a high concentration of tyramine or dopamine. Therefore, patients
being treated with NARDIL should avoid high protein food that has undergone protein
breakdown by aging, fermentation, pickling, smoking, or bacterial contamination.
