Xylazine ("tranq")

A veterinary sedative (alpha-2 agonist) found as an adulterant in illicit fentanyl; approved only for animal use, not for humans.

psilodex.org/m/xylazine · data v2026.10.04

Clinical contraindication: None listed; No clinical contraindication identified.
Psilocybin evidence: No psilocybin data
Half-life: Not stated in label or references

Named in state rules?

Not namedColorado

Not namedOregon

PendingNew Mexico

Cite asPsilodex, “Xylazine ("tranq")”, v2026.10.04. psilodex.org/m/xylazine

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

What it is used for

FDA status

Not FDA-approved

Xylazine is FDA-approved for veterinary use only; not approved for humans.

Availability

Illicit

01 Interaction with psilocybin

No psilocybin data; an animal sedative in street fentanyl causing deep sedation, slow heart rate and low blood pressure that naloxone does not reverse.

Detail Veterinary alpha-2 sedative found mostly in illicit fentanyl. It causes deep, prolonged sedation, slow heart rate and low blood pressure that naloxone does not reverse, though naloxone still reverses co-present opioids. Withdrawal has been reported after chronic use. Sources [1][2][3]

Human data with psilocybin: None known: no published human data with psilocybin

Evidence types on this record

No psilocybin dataNo psilocybin data; record based on general references (product label, reference works, reviews)

02 Pharmacology relevant to psilocybin

3 listed · counted on reports

Sedating or CNS depressant: Slows the central nervous system: drowsiness, slower reactions and impaired coordination, and slowed breathing at high doses. Effects add with other sedating substances. Sources [1]
Withdrawal or rebound if stopped abruptly: Stopping suddenly can cause withdrawal or a rebound of symptoms. Sources [3]
Lowers blood pressure or causes orthostasis: Lowers blood pressure, or causes a drop on standing (orthostasis) that can bring dizziness or fainting. 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 2026-10-02

04 Conditions to ask about

None linked

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

05 Sources

National Institute on Drug Abuse (NIDA), NIH. Research-topic pages (per-entry link). — CNS depressant; breathing, heart rate and blood pressure can slow to dangerously low levels; naloxone does not reverse xylazine
US Drug Enforcement Administration. 2025 National Drug Threat Assessment. May 2025. — xylazine veterinary-only; 'rhino tranq' medetomidine 200–300x xylazine potency (pp. 30–32)
StatPearls (NCBI Bookshelf), drug monograph Indications section (per-drug link) — discontinuation_risk: Management of Xylazine Withdrawal Symptoms "Withdrawal symptoms have been reported in cases of chronic xylazine use."

Record history

v2026.10.02First published.
2026-10-03Last reviewed against its sources.

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