Nardil Tapering Guide
phenelzine
Boxed Warning
Suicidality risk in children, adolescents, and young adults under 25 during initial antidepressant treatment.
Overview
Phenelzine is a non-selective irreversible monoamine oxidase inhibitor (MAOI). Effective for atypical depression, treatment-resistant depression, and panic — but rarely used today because of strict dietary restrictions and dangerous drug interactions.
15mg tablets
Tablets: 15mg
Category C
Mechanism of Action
Irreversibly binds and inactivates MAO-A and MAO-B, blocking the breakdown of serotonin, norepinephrine, dopamine, and tyramine.
Taper Notes
Very slow taper required. Even after the last dose, MAO inhibition persists for ~2 weeks. Do NOT switch directly to another antidepressant — full 14-day washout required.
Hyperbolic Tapering Guidance
MAOIs are the hardest antidepressants to discontinue safely. Plan washout windows carefully when transitioning to or from any other agent.
Summary written by TaperCommunity, informed by the Maudsley Deprescribing Guidelines (Horowitz & Taylor) and related literature — see Sources & References below. Not affiliated with or endorsed by the Maudsley.
Withdrawal Timeline
1-5 days after stopping
1-3 weeks
4-8 weeks (MAO enzyme regeneration takes ~2 weeks)
Sleep architecture and mood reactivity can take 2-3 months to renormalize
Common Withdrawal Symptoms
Interactions & Safety
Drug Interactions
- SSRIs, SNRIs, TCAs, triptans, tramadol, meperidine, dextromethorphan, St John's Wort — contraindicated (serotonin syndrome / hypertensive crisis)
- Sympathomimetics (decongestants, stimulants) — hypertensive crisis
- Other MAOIs — contraindicated
Contraindications
- Pheochromocytoma
- Concurrent use of any other MAOI, SSRI, SNRI, TCA, or serotonergic drug (washout periods 14 days, longer for fluoxetine)
- Tyramine-rich diet (requires strict patient education)
Toxicity
Hypertensive crisis with tyramine-rich foods (aged cheese, cured meats, tap beer, fermented soy, broad beans). Serotonin syndrome with serotonergic agents. Significant overdose risk.
Pharmacokinetics
ADME Profile
Hepatic.
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Other Drug Profiles
Sources & References
Nardil (phenelzine) information on this page is sourced from peer-reviewed research, regulatory bodies, clinical guidelines, and patient-advocacy organizations.
Encyclopedic & chemical databases
Neutral, high-authority entity references.
Regulatory sources
Official prescribing information and safety notices.
Peer-reviewed research
Primary literature cited in this taper guide.
- Horowitz MA, Taylor D 2019 — Tapering of SSRI treatment to mitigate withdrawal symptoms (hyperbolic taper) (The Lancet Psychiatry)
- Davies J, Read J 2019 — A systematic review into the incidence, severity and duration of antidepressant withdrawal effects (Addictive Behaviors)
- Framer A 2021 — The patient voice: an exploration of the experience of withdrawal from antidepressants (Therapeutic Advances in Psychopharmacology)
Clinical guidelines
Evidence-based deprescribing and prescribing standards.
Deprescribing-specific resources
Clinician-facing references on tapering protocols.
- Deprescribing.org — Evidence-based deprescribing algorithms from the Bruyère Research Institute
- Royal College of Psychiatrists — Stopping antidepressants — UK clinical guidance on safely discontinuing antidepressants
Patient-advocacy & lived-experience
Long-running communities documenting withdrawal experience.
- Surviving Antidepressants — tapering forum — Long-running community archive of antidepressant taper experiences
- Inner Compass Initiative — Withdrawal Project — Peer-led resources for psychiatric drug withdrawal
- Mad in America — antidepressant withdrawal archive — Journalism and personal narratives on SSRI/SNRI discontinuation
- RxISK — adverse drug reaction reporting — Independent database of patient-reported adverse effects
TaperCommunity does not provide medical advice. Always consult a qualified prescriber before adjusting psychiatric medication.