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3-HO-PCP Facts

Dissociative; Arylcyclohexylamine; NMDA receptor antagonist

Description

3-HO-PCP (3-hydroxyphencyclidine) is a synthetic dissociative of the arylcyclohexylamine class. It blocks glutamate signaling in the brain while simultaneously activating opioid receptors — a combination not found in other common dissociatives.[1][2]

Subjective effects include perceptual disconnection, derealization, analgesia, euphoria, and a bodily warmth and heaviness that most dissociatives do not produce. The experience is defined by opioid-type sedation layered over dissociative detachment — warmer and more sedating than ketamine, and unlike anything else in the arylcyclohexylamine class.

The opioid activity means physical dependence is a real risk with repeated use,[1] and no lethal dose has been established in any species.[3] Combining it with opioids, alcohol, or sedatives amplifies respiratory depression far beyond what either produces alone — every documented serious case involved a co-present depressant.[4]

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 1 mgLight2 – 4 mgCommon4 – 6 mgStrong6 – 8 mgHeavy8+ mg

Starts in 30 – 45 minLasts 4 – 6 hoursAfter-effects 2 – 4 hours

Body and dependence

Acute toxicity
Moderate
Chronic toxicity
Moderate
Physical dependence
Moderate
Psychological dependence
Moderate
Withdrawal
Moderate
Compulsive redosing
Moderate

Tolerance

Builds
Moderate
Fully resets after
10 days
Carries over to
dissociatives; opioids

Effectslikely at a common dose

Perception
none likely · 15 possible, including Vestibular distortion, Spatial disorientation, Double vision
Body
Nystagmus (eye wobbles); Pain suppression; Motor control impairment; +21 possible, including Dizziness, Nausea, Temperature dysregulation
Thinking
Cognitive impairment; +16 possible, including Thought disorganization, Confusion, Decision impairment
Feeling
none likely · 6 possible, including Anxiety, Dysphoria, Paranoia
Self
Depersonalization; Derealization; +4 possible, including Communication suppression, Craving, Social disconnection
Time
none likely · 2 possible, including Temporal disorientation

Who shouldn't take it

Absolute
Respiratory insufficiency; Psychotic disorders; Pregnancy; Concurrent opioid use
Relative
Cardiovascular disease; Bipolar disorder; Hepatic impairment; Concurrent benzodiazepine use; History of opioid dependence

Combinations60 recorded

Lethal (4)
Benzodiazepines, Barbiturates; GHB, Baclofen; GHB, GBL; Local anesthetics
Dangerous (34)
Alpha-2 adrenergic receptor antagonist; Amphetamines; Benzodiazepines; Buprenorphine, Kratom; Cannabis, THC; Gabapentin, Pregabalin; MDMA, Amphetamines; Naltrexone; NRIs; NSAIDs; Stimulants; THC; Anticholinergics; Antihistamines; Atypical antipsychotics; Buspirone; Caffeine; CBD; Clonidine, Guanfacine; Dopamine agonists; Glutamate modulator; Huperzine A; Ibogaine; Ketamine, DXM, PCP; and 10 more, see full page
Caution (18)
See full page: psychedex.org/substances/3-ho-pcp
Not graded (4)
Not listed never means safe.

Seek help immediately if

  • Severe disorientation; unable to move or speak (deep dissociation / "k-hole")
  • Complete loss of coordination — cannot stand or walk safely
  • Vomiting while incapacitated (choking / aspiration risk)
  • Very high blood pressure; fast heart rate
  • Slow or shallow breathing at high doses (especially mixed with depressants)
  • Unconsciousness; rarely, seizures

What to do

  1. Move them somewhere safe, away from stairs, water, roads, and sharp edges — they cannot protect themselves
  2. Place in the recovery position if vomiting or unconscious (aspiration is a key risk)
  3. Stay with them and reassure calmly; keep the environment quiet
  4. If breathing is slow/shallow or they are unresponsive, call emergency services
  5. Do not let them wander; do not leave them alone
  6. Be ready to give rescue breaths / CPR

Effects wear off with time in a safe, monitored setting. The main dangers are physical injury and aspiration while incapacitated, and respiratory depression when combined with other depressants — not the dissociation itself.

988 Suicide & Crisis LifelineFireside Project: 62-FIRESIDE

Version r1 · Not medical advice

References

  1. [1]
    ^abHandWiki contributors (2023) 3-HO-PCP - HandWiki Link
  2. [2]
    ^Luethi D, Liechti ME (2020) Designer drugs: mechanism of action and adverse effects — Archives of Toxicology doi:10.1007/s00204-020-02693-7
  3. [3]
    ^WHO Expert Committee on Drug Dependence (2024) 3-OH-PCP 47th ECDD Critical Review (Public Version) Link
  4. [4]
    ^Levinstein MR, Budinich RC, Bonaventura J, Schatzberg AF, Zarate CA, Michaelides M (2025) Redefining Ketamine Pharmacology for Antidepressant Action: Synergistic NMDA and Opioid Receptor Interactions — American Journal of Psychiatry doi:10.1176/appi.ajp.20240378
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