Dosing and uses of Nardil (phenelzine)
Adult dosage forms and strengths
tablet
- 15mg
Depression
Initial 15 mg PO q8hr, increase not to exceed 20-30 mg q8hr
Decrease dose after maximum response (2-6 weeks) over 2-6 week period to maintain dose as low as 15 mg qDay or every other day
Monitor blood pressure
Pediatric dosage forms and strengths
Safety & efficacy not established
Geriatric dosage forms and strengths
Depression
Initial 15 mg PO q8hr, increase not to exceed 20-30 mg q8hr
Decrease dose after maximum response (2-6 weeks) over 2-6 week period to maintain dose as low as 15 mg qDay or every other day
Monitor blood pressure
Nardil (phenelzine) adverse (side) effects
Frequency not defined
Common
- Orthostatic hypotension
- Asthenia
- Dizziness
- Headache
- Drowsiness
- Fatigue
- Hyperreflexia
- Sleep disturbance
- Somnolence
- Weakness
- Tremor
- Constipation
- Dry mouth
- Weight gain
Less Common
- Confusion
- Decreased memory
- Paresthesia
- Anorexia
- Nausea
- Vomiting
- Impotence
- Increased LFT's
- Nystagmus
- Urinary frequency or retention
Uncommon
- Edema
- Anxiety
- Irritation
- Hypomania
- Hypermetabolic syndrome (hyperpyrexia, tachycardia, tachypnea, increased CPK, acidosis)
- Arthralgia
- SIADH
Rare
- Hypertensive crisis
- Ataxia
- Seizure
- Worsening depression
- Suicide
- Edema of glottis
- Leukopenia
- Hepatic necrosis, jaundice
- Drug-induced lupus erythematosus
- Visual disturbance
Warnings
Black box warnings
In short-term studies, antidepressants increased the risk of suicidal thinking and behavior in children, adolescents, and young adults (<24 yr of age) taking antidepressants for major depressive disorders and other psychiatric illnesses
This increase was not seen in patients aged >24 years; a slight decrease in suicidal thinking was seen in adults >65 years
In children and young adults, risks must be weighed against the benefits of taking antidepressants
Patients should be monitored closely for changes in behavior, clinical worsening, and suicidal tendencies; this should be done during initial 1-2 months of therapy and dosage adjustments
The patient’s family should communicate any abrupt changes in behavior to the healthcare provider
Worsening behavior and suicidal tendencies that are not part of the presenting symptoms may require discontinuation of therapy
This drug is not approved for use in pediatric patients
Contraindications
Hypersensitivity
Pheochromocytoma, CHF, HTn
Concomitant sympathomimetic drugs, meperidine, dextromethorphan
Liver disease, abnormal liver function tests
Severe renal impairment, ESRd
Elective surgery using general anesthesia
Cautions
Clinical worsening & suicide ideation may occur despite medication in adolescents & young adults (18-24 yo)
Hypertensive reactions may occur from consumption of foods high in tyramine or supplements containing caffeine, tyrosine, tryptophan, phenylalanine, or phenylalanine
Orthostatic hypotension may occur
Discontinue STAT at signs/symptoms of hypertensive crisis, eg, palpitations, occipital HA, N/V
Caution in patients with diabetes mellitus (monitor glucose closely), glaucoma, hepatic/renal impairment, history of seizures, thyroid dysfunction
Bipolar disorder
Hypertensive reactions may occur from consumption of foods high in tyramine or supplements containing caffeine, tyrosine, tryptophan, phenylalanine, or phenylalanine
Not first-line therapy
Discontinue 10 days before surgery
Pregnancy and lactation
Pregnancy category: C
Lactation: unknown; use caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Nardil (phenelzine)
Mechanism of action
Nonselective monoamine oxidase inhibitor; may inhibit the enzyme monoamine oxidase, which is responsible for the breakdown of dopamine, serotonin, epinephrine, and norepinephrine, in turn causing an increase in endogenous concentrations of these neurotransmitters.
Pharmacokinetics
Peak Plasma Time: 43 min
Metabolism: by MAO
Onset of action: 2-4 weeks
Duration: Therapeutic effects and interactions may continue for up to 2 weeks after discontinuing therapy
Metabolites: phenylacetic acid & parahydroxyphenylacetic acid
Half-Life, Elimination: 11.6 hr
Excretion: Urine
