Tranylcypromine

Clinical contraindication: Absolute; The clinical literature treats the combination as contraindicated.
Best available evidence: Controlled trial; Also: case reports, other psychedelic.
Half-life: 24 h; Approximate, in adults. Detail in 01.

Named in state rules?

CONot named

ORNot named

NMPending

Cite asPsilodex: tranylcypromine · v2026.10.02

Clinical data and state rules are separate facts. Both are shown; neither is a decision.

01 Interaction with psilocybin

RCT · CR · XP

In a small controlled study, tranylcypromine pretreatment increased psilocybin's blood-pressure and pupil effects without significantly reducing subjective effects (Vojtěchovský 1968). One case report describes a hypertensive emergency and myocardial infarction after mushrooms taken during tranylcypromine plus extended-release amphetamine (Barnett 2024). With LSD, chronic MAOIs nearly abolished the response in 2 of 2 people (Bonson & Murphy 1996). MAO-A contributes to psilocin clearance (Thomann 2024); serotonin toxicity is theoretical, with no reported human case.

Human data with psilocybin: Human studies with psilocybin
Common practice: Where discontinuation is considered, product labeling describes a washout of at least two weeks before starting a serotonergic drug. Any change is prescriber-managed.
Half-life: eliminated within 24 h; MAO recovery 3–5 days, inhibition may persist up to 10 days (FDA label, checked 2026-09-30)

Evidence types on this record

RCTControlled trial

CRCase reports or online surveys

XPHuman data with another classic psychedelic (e.g. LSD), not psilocybin; named in the text

02 Pharmacology relevant to psilocybin

3 listed · counted on reports

MAO inhibition: Inhibits monoamine oxidase, the enzyme that breaks down serotonin and other monoamines. MAO also helps clear psilocin, so it can change how strong and how long the psilocybin effect is, and it raises serotonin levels. Sources [1]
Raises blood pressure or heart rate: Raises blood pressure or heart rate. Psilocybin raises both for several hours, so the effects can add. Sources [1]
Serotonergic: Increases serotonin activity, for example by blocking its reuptake or releasing it. Psilocybin acts on serotonin receptors, so effects can add together. With antidepressant use, the psilocybin response can be weaker. Sources [1]

03 State rules

Plain-language summary · official text governs

CO4 CCR 755-1

Not named

No provision names this medication or its class.

Colorado · checked 2026-09-30

OROAR 333-333

Not named

No provision names this medication or its class.

Oregon · checked 2026-09-30

NM7.35.3 NMAC (proposed)

Pending

New Mexico's clinical rules (proposed 7.35.3 NMAC) are not final. No provision naming this medication has been found.

New Mexico · checked 2026-09-30

04 Conditions to ask about

None linked

No condition named in state rules is linked to this medication.

05 Sources

Tranylcypromine — prescribing information · FDA label (DailyMed)
Vojtěchovský M, Hort V, Šafratová V. Influence of MAO inhibitors on psilocybine induced psychosis. Activitas Nervosa Superior 1968;10(3):278–279 (via Tap 2025).
Barnett BS, Koons CJ, Van den Eynde V, et al. Hypertensive emergency secondary to combining psilocybin mushrooms, extended release dextroamphetamine-amphetamine, and tranylcypromine. J Psychoactive Drugs 2024;57(3):297–303.
Bonson KR, Murphy DL. Alterations in responses to LSD in humans associated with chronic administration of tricyclic antidepressants, monoamine oxidase inhibitors or lithium. Behav Brain Res 1996;73:229–233.
Thomann J, Kolaczynska KE, Stoeckmann OV, et al. In vitro and in vivo metabolism of psilocybin’s active metabolite psilocin. Front Pharmacol 2024;15:1391689.

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