Phenelzine
NARDIL
Pronunciation: FEN-el-zeen
“Gnarly Funnel”
Mao Zedong → MAO inhibitor
What it isIrreversible MAO-A and MAO-B inhibitor; atypical and treatment-resistant depression.
Why this oneCompared with tranylcypromine it is more sedating and weight-promoting, but often favored when anxiety dominates.
What limits it⚑ Tyramine can trigger hypertensive crisis, and serotonergic combinations can be fatal; observe drug-specific washout intervals.
FDA-approved for
- depression (~1961)
Off-label
- social anxiety disorder
- panic disorder
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Depression | Adult | 15 mg TID | 60 mg/day (increase rapidly per tolerance) | 90 mg/day |
Renal Contraindicated in severe renal impairment/disease
Hepatic Contraindicated in liver disease or abnormal LFTs
Maintenance dose may be as low as 15 mg daily or every other day.
Instructions
- Taper slowly over several weeks after maximum benefit
- Avoid high-tyramine foods (aged cheese, cured/fermented meats, tap beer, wine, fava beans, yeast extract)
- Allow >=14 days washout before/after other MAOIs or serotonergic agents; discontinue >=10 days before elective surgery
Available strengths
- tab 15 mg
Contraindications
- Pheochromocytoma
- Congestive heart failure
- Severe renal impairment or renal disease
- History of liver disease or abnormal liver function tests
- Sympathomimetics (amphetamines, cocaine, methylphenidate, dopamine, epinephrine, norepinephrine) and related compounds (methyldopa, L-dopa, L-tryptophan, L-tyrosine, phenylalanine)
- High-tyramine foods (risk of hypertensive crisis)
- Other MAO inhibitors; buspirone
- Meperidine
- Dextromethorphan; CNS depressants (alcohol, narcotics)
- Serotonergic agents (SSRIs/SNRIs) — risk of serotonin syndrome
- Bupropion
- Guanethidine
- Elective surgery requiring general anesthesia; cocaine or local anesthetics with sympathomimetic vasoconstrictors
Cautions
- Hypertensive crisis with tyramine foods or sympathomimetics
- Serotonin syndrome with serotonergic drugs
- Suicidality in young patients (boxed)
- Postural hypotension
Adverse reactions
- Dizziness, headache, drowsiness, sleep disturbance
- Postural hypotension, edema
- Weight gain, dry mouth, constipation
- Sexual dysfunction (anorgasmia, ejaculatory disturbance, impotence)
- Elevated serum transaminases
Pregnancy Undefined
Lactation Undefined
Cost
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 15 mg | tab | 90 TID | $52.76 | offered |
Generic entry2010
⚠ BOXED WARNING
- Suicidal thoughts and behaviors in patients under 25
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityHypertensive crisis and serotonin toxicity can occur with interacting foods or drugs; washout periods are essential.
Serotonin and MAOI
Provisional washout figures
Elevating mechanismMAO-A inhibitor
Non-elevating actionNone recorded
Exposure dependenceTherapeutic exposure
Washout AFTER an MAOI14 days
Evidence confidenceHigh
InterpretationNonselective irreversible MAOI; defining high-risk partner for significant SRIs.
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