Supplements and over the counter

Brand names
Delsym, Robitussin DM, Mucinex DM, NyQuil, DayQuil, Coricidin HBP Cough & Cold, Vicks 44

Reviewed 2026-09-30

Dextromethorphan

Clinical contraindication: None listed; No clinical contraindication identified.
Best available evidence: Mechanism only
Half-life: ~2–3 h; Approximate, in adults. Detail in 01.

Named in state rules?

CONot named

ORNot named

NMPending

Cite asPsilodex: dextromethorphan · v2026.10.02

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

01 Interaction with psilocybin

Serotonergic plus dissociative.

Human data with psilocybin: None known: no published human data with psilocybin
Half-life: ~2–3 h; ~15–20 h in CYP2D6 poor metabolizers (~8–10% of some populations); about 3× longer alongside bupropion, a CYP2D6 inhibitor (StatPearls (NCBI Bookshelf); Auvelity FDA label for the bupropion effect, checked 2026-10-01)

Evidence types on this record

ThMechanism only (theoretical)

1 listed · counted on reports

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]

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

None linked

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