Selegiline

Clinical contraindication: Absolute; The clinical literature treats the combination as contraindicated.
Best available evidence: Mechanism only
Half-life: 10 h; Approximate, in adults. Detail in 01.

Named in state rules?

CONot named

ORNot named

NMPending

Cite asPsilodex: selegiline · v2026.10.02

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

01 Interaction with psilocybin

MAO-B selective at usual doses, losing selectivity at higher doses or transdermally; may then increase psilocin exposure (MAO-A is one clearance route). MAO inhibition can raise blood pressure with psilocybin (see tranylcypromine); serotonin toxicity is theoretical, with no reported human case.

Human data with psilocybin: None known: no published human data 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: oral 10 h steady state; Emsam 18–25 h (FDA label, checked 2026-09-30)

Evidence types on this record

ThMechanism only (theoretical)

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 [2]

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

Selegiline Hydrochloride Tablets USP 5 mg · FDA label (DailyMed)
Preston CL (ed). Stockley’s Drug Interactions, 11th ed. Pharmaceutical Press, 2016., p. 659
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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