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Psychedex
Facts label

Trihexyphenidyl Facts

Deliriant; Substituted piperidine; Muscarinic acetylcholine receptor antagonist

Dose and duration

No dose or duration recorded for any route.

Body and dependence

Acute toxicity
Not assessed
Chronic toxicity
Not assessed
Physical dependence
Not assessed
Psychological dependence
Not assessed
Withdrawal
Not assessed
Compulsive redosing
Not assessed

Tolerance

Not recorded.

Who shouldn't take it

None recorded. Not listed never means safe to take.

Combinations60 recorded

Dangerous (18)
Amphetamines; Antihistamines; Antipsychotics; Atypical antipsychotics; Buprenorphine, Kratom; GHB, GBL; MDMA, MDA; Naltrexone; Opioids; Ephedrine, Pseudoephedrine; GHB, Baclofen; Ibogaine; Ketamine, DXM, PCP; Local anesthetics; NDRIs (Wellbutrin); Salvia, Ibogaine; SSRIs; Stimulants
Caution (35)
See full page: psychedex.org/substances/trihexyphenidyl
Not graded (7)
Not listed never means safe.

Seek help immediately if

Deliriants are genuinely dangerous — treat any strong reaction as a medical emergency.

  • True delirium — confused, disoriented, doesn't know what's real or recognize people/danger
  • Vivid, frightening hallucinations; agitation or aggression
  • Hot, flushed, dry skin and high body temperature
  • Dilated pupils; blurred vision
  • Fast heartbeat; inability to urinate
  • Seizures; unconsciousness

What to do

  1. Call emergency services — deliriant poisoning (especially datura / belladonna) can be life-threatening
  2. Keep them physically safe — they may not know what they're doing and can badly injure themselves; remove hazards and stay with them
  3. Do not leave them alone; do not try to reason them out of it — they are delirious
  4. If overheating, cool the body
  5. Recovery position if drowsy, vomiting, or unconscious; be ready for rescue breaths / CPR

Deliriant effects are long (many hours to more than a day) and the person is not safe or in control throughout. The main dangers are self-injury during delirium, overheating, and — for potent anticholinergics like datura — cardiac and central-nervous-system toxicity. Medical monitoring is often needed.

988 Suicide & Crisis LifelineFireside Project: 62-FIRESIDE

psychedex.org/substances/trihexyphenidyl · Version r1 · Not medical adviceValues as of