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Psychedex
Sources
30
6 strong · 20 moderate · 4 weak

Studies and references cited across this article, graded by evidence strength.

Claims checked
79
49verified8partial19inconclusive3not supported

Inconclusive means the cited source neither confirms nor refutes the claim — a lower-confidence badge, not an error.

Generated
Apr 27, 2026 · pipeline-v5
Values approved
175/175 (100%)

Data points an editor reviewed and accepted for publication.

01

Value Provenance

Dosing

smokedtrace

FieldPublishedAI ProposedConfidence
Threshold1 mg1 mglow
Low2–5 mg2–5 mglow
Common5–10 mg5–10 mglow
Strong10–15 mg10–15 mglow
Heavy15+ mg15+ mglow
Editorial

Proposed from ACNP reference (1-2 mg IV/inhaled in experimental settings produce initial effects) and StatPearls (effects begin at 0.05 mg/kg; 20 mg+ produces severe toxicity). No controlled recreational dose-response studies exist. Ranges represent best estimate from clinical literature extrapolation.

Reasoning

Proposed from ACNP reference (1-2 mg IV/inhaled in experimental settings produce initial effects) and StatPearls (effects begin at 0.05 mg/kg; 20 mg+ produces severe toxicity). No controlled recreational dose-response studies exist. Ranges represent best estimate from clinical literature extrapolation.

Evidence basis: expert_opinion

insufflatedtrace

FieldPublishedAI ProposedConfidence
Threshold1 mg1 mglow
Low2–5 mg2–5 mglow
Common5–10 mg5–10 mglow
Strong10–15 mg10–15 mglow
Heavy15+ mg15+ mglow
Editorial

Assumed similar to smoked route based on comparable absorption kinetics. Insufflation is documented as a common ROA in the literature. No specific dose-response data for insufflated PCP located.

Reasoning

Assumed similar to smoked route based on comparable absorption kinetics. Insufflation is documented as a common ROA in the literature. No specific dose-response data for insufflated PCP located.

Evidence basis: expert_opinion

oraltrace

FieldPublishedAI ProposedConfidence
Threshold2 mg2 mglow
Low3–7 mg3–7 mglow
Common7–12 mg7–12 mglow
Strong12–20 mg12–20 mglow
Heavy20+ mg20+ mglow
Editorial

Oral bioavailability is ~72% (Cook et al. 1982), suggesting slightly higher doses needed than inhaled routes for equivalent effect. StatPearls notes 20 mg+ produces severe toxicity. Upper end of heavy range aligned with clinical toxicity threshold.

Reasoning

Oral bioavailability is ~72% (Cook et al. 1982), suggesting slightly higher doses needed than inhaled routes for equivalent effect. StatPearls notes 20 mg+ produces severe toxicity. Upper end of heavy range aligned with clinical toxicity threshold.

Evidence basis: expert_opinion

Duration

smoked

FieldPublishedAI ProposedConfidence
Onsettrace1–5 minutes1–5 minutesmedium
Editorial

ACNP and StatPearls report onset 2-5 minutes for inhalation/IV route.

Reasoning

ACNP and StatPearls report onset 2-5 minutes for inhalation/IV route.

Evidence basis: expert_opinion

Totaltrace4–8 hours4–8 hoursmedium
Editorial

ACNP reports 4-8 hours primary intoxication at recreational doses.

Reasoning

ACNP reports 4-8 hours primary intoxication at recreational doses.

Evidence basis: expert_opinion

After effectstrace12–48 hours12–48 hoursmedium
Editorial

Residual effects documented for up to 48 hours in overdose (StatPearls). Lipophilic redistribution produces sustained aftereffects.

Reasoning

Residual effects documented for up to 48 hours in overdose (StatPearls). Lipophilic redistribution produces sustained aftereffects.

Evidence basis: expert_opinion

insufflated

FieldPublishedAI ProposedConfidence
Onsettrace2–10 minutes2–10 minuteslow
Editorial

ACNP describes intranasal onset as 'several minutes'. Less direct data than smoked route.

Reasoning

ACNP describes intranasal onset as 'several minutes'. Less direct data than smoked route.

Evidence basis: expert_opinion

Totaltrace4–8 hours4–8 hourslow
Editorial

Assumed similar to smoked route. No specific insufflated duration data located.

Reasoning

Assumed similar to smoked route. No specific insufflated duration data located.

Evidence basis: expert_opinion

After effectstrace12–48 hours12–48 hourslow
Editorial

Inferred from smoked route and general PCP pharmacokinetics (long half-life, lipophilic redistribution).

Reasoning

Inferred from smoked route and general PCP pharmacokinetics (long half-life, lipophilic redistribution).

Evidence basis: expert_opinion

oral

FieldPublishedAI ProposedConfidence
Onsettrace20–60 minutes20–60 minutesmedium
Editorial

ACNP and StatPearls report oral onset 20-60 minutes.

Reasoning

ACNP and StatPearls report oral onset 20-60 minutes.

Evidence basis: expert_opinion

Come uptrace30–60 minutes30–60 minuteslow
Editorial

Inferred from oral onset to peak time of ~90 minutes (ACNP). Come-up follows onset period.

Reasoning

Inferred from oral onset to peak time of ~90 minutes (ACNP). Come-up follows onset period.

Evidence basis: expert_opinion

Peaktrace1.5–3 hours1.5–3 hourslow
Editorial

Inferred from peak plasma at ~90 minutes and total duration 4-8 hours.

Reasoning

Inferred from peak plasma at ~90 minutes and total duration 4-8 hours.

Evidence basis: expert_opinion

Totaltrace4–8 hours4–8 hoursmedium
Editorial

ACNP reports 4-8 hours primary intoxication at recreational doses. Applies across routes.

Reasoning

ACNP reports 4-8 hours primary intoxication at recreational doses. Applies across routes.

Evidence basis: expert_opinion

After effectstrace12–48 hours12–48 hoursmedium
Editorial

Residual effects documented up to 48 hours. Long half-life (17-21 hours) and high oral bioavailability (72%) produce sustained plasma levels.

Reasoning

Residual effects documented up to 48 hours. Long half-life (17-21 hours) and high oral bioavailability (72%) produce sustained plasma levels.

Evidence basis: expert_opinion

Safety

Toxicity Profiletrace

FieldPublishedAI ProposedConfidence
Acutehighhighhigh
Chronichighhighhigh
Organs Affectedcardiovascular, kidney, liver, musculoskeletal, neurologicalcardiovascular, kidney, liver, musculoskeletal, neurologicalhigh
Editorial

Acute toxicity classified as high based on StatPearls 2023 clinical data: rhabdomyolysis 70%, hypertension 60%, seizures above 20 mg, documented fatalities. Chronic toxicity classified as high based on documented cognitive impairment, persistent psychotic symptoms, and NMDA receptor adaptations (Hanania et al. 1999). Multiple independent human case series support both classifications.

Reasoning

Acute toxicity classified as high based on StatPearls 2023 clinical data: rhabdomyolysis 70%, hypertension 60%, seizures above 20 mg, documented fatalities. Chronic toxicity classified as high based on documented cognitive impairment, persistent psychotic symptoms, and NMDA receptor adaptations (Hanania et al. 1999). Multiple independent human case series support both classifications.

Evidence basis: published_case_series

Dependence Profiletrace

FieldPublishedAI ProposedConfidence
Physicallowlowmedium
Psychologicalmoderatemoderatemedium
Compulsive Redosingmoderatemoderatemedium
Dose Escalationmoderatemoderatemedium
Editorial

Positive reinforcement confirmed by animal self-administration (Nicholson et al. 2007). Withdrawal syndrome demonstrated in rats after continuous infusion (Berquist et al. 2018). Human dependence data limited to anecdotal reports. Murray 2002 explicitly notes that addictive potential is unclear due to restricted study population.

Reasoning

Positive reinforcement confirmed by animal self-administration (Nicholson et al. 2007). Withdrawal syndrome demonstrated in rats after continuous infusion (Berquist et al. 2018). Human dependence data limited to anecdotal reports. Murray 2002 explicitly notes that addictive potential is unclear due to restricted study population.

Evidence basis: animal_study

Withdrawal Profiletrace

FieldPublishedAI ProposedConfidence
Severitymildmildlow
Symptomscraving, anxiety, dysphoria, tremors, facial muscle twitching, diarrhoeacraving, anxiety, dysphoria, tremors, facial muscle twitching, diarrhoealow
FatalNoNolow
Medical SupervisionNot requiredNot requiredlow
Editorial

Withdrawal features described anecdotally in chronic heavy human users. Animal model (Berquist et al. 2018) demonstrated disruption of operant responding after cessation of continuous PCP infusion, reversed by MXE. No formal controlled withdrawal characterisation in humans.

Reasoning

Withdrawal features described anecdotally in chronic heavy human users. Animal model (Berquist et al. 2018) demonstrated disruption of operant responding after cessation of continuous PCP infusion, reversed by MXE. No formal controlled withdrawal characterisation in humans.

Evidence basis: animal_study

Tolerance Profiletrace

FieldPublishedAI ProposedConfidence
Buildupmoderatemoderatelow
Half-life——low
Full Reset——low
Cross-tolerancesketamine, dextromethorphan, MK-801, methoxetamineketamine, dextromethorphan, MK-801, methoxetaminelow
Editorial

Tolerance mechanism characterised in animal models (Hanania et al. 1999) showing NR1 upregulation and locomotor sensitisation. Human tolerance time-course not established. Cross-tolerance with NMDA antagonists inferred from shared PCP binding site. Murray 2002 flags tolerance characterisation as an unresolved question.

Reasoning

Tolerance mechanism characterised in animal models (Hanania et al. 1999) showing NR1 upregulation and locomotor sensitisation. Human tolerance time-course not established. Cross-tolerance with NMDA antagonists inferred from shared PCP binding site. Murray 2002 flags tolerance characterisation as an unresolved question.

Evidence basis: animal_study

Effects & Profile

Contraindications

FieldPublishedAI ProposedConfidence
pregnancy breastfeeding pregnancytraceabsoluteabsolutemedium
Editorial

PCP's high lipophilicity (XLogP 4.22) ensures placental transfer. Neonatal effects reported in exposed populations, though controlled human data are limited.

Reasoning

PCP's high lipophilicity (XLogP 4.22) ensures placental transfer. Neonatal effects reported in exposed populations, though controlled human data are limited.

psychiatric psychotic disorderstraceabsoluteabsolutehigh
Editorial

Lahti et al. 2001 demonstrated ketamine/PCP-class compounds specifically exacerbate individual psychotic symptom profiles. Javitt & Zukin 1991 established PCP as the most complete pharmacological model of schizophrenia.

Reasoning

Lahti et al. 2001 demonstrated ketamine/PCP-class compounds specifically exacerbate individual psychotic symptom profiles. Javitt & Zukin 1991 established PCP as the most complete pharmacological model of schizophrenia.

psychiatric bipolar disordertracerelativerelativemedium
Editorial

Inferred from PCP's strong dopaminergic profile (D2High Ki 2.7 nM, DAT competition confirmed by PET) and general class-level risk of dopaminergic agents in bipolar disorder.

Reasoning

Inferred from PCP's strong dopaminergic profile (D2High Ki 2.7 nM, DAT competition confirmed by PET) and general class-level risk of dopaminergic agents in bipolar disorder.

neurological epilepsytraceabsoluteabsolutehigh
Editorial

StatPearls 2023 documents dose-dependent seizures in PCP intoxication. Absolute contraindication due to direct proconvulsant effect.

Reasoning

StatPearls 2023 documents dose-dependent seizures in PCP intoxication. Absolute contraindication due to direct proconvulsant effect.

cardiovascular hypertensiontraceabsoluteabsolutehigh
Editorial

StatPearls 2023 reports hypertension in 60% and tachycardia in 30% of PCP intoxication cases. Intraparenchymal and subarachnoid haemorrhage are documented complications.

Reasoning

StatPearls 2023 reports hypertension in 60% and tachycardia in 30% of PCP intoxication cases. Intraparenchymal and subarachnoid haemorrhage are documented complications.

renal renal impairmenttraceabsoluteabsolutehigh
Editorial

StatPearls 2023 reports rhabdomyolysis in 70% of PCP intoxication cases. Acute kidney injury is a well-documented complication.

Reasoning

StatPearls 2023 reports rhabdomyolysis in 70% of PCP intoxication cases. Acute kidney injury is a well-documented complication.

hepatic hepatic impairmenttracerelativerelativemedium
Editorial

Cook et al. 1982/1983 established hepatic metabolism as the primary elimination route. StatPearls reports LFT elevation in 50% of cases. Impaired clearance would amplify all PCP toxicity risks.

Reasoning

Cook et al. 1982/1983 established hepatic metabolism as the primary elimination route. StatPearls reports LFT elevation in 50% of cases. Impaired clearance would amplify all PCP toxicity risks.

Timeline Phases

smoked

FieldPublishedAI ProposedConfidence
Plateautrace5400–10800 sec(i=0.50)5400–10800 sec(i=0.50)medium
Editorial

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Reasoning

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Come uptrace300–900 sec(i=0.30)300–900 sec(i=0.30)medium
Editorial

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Reasoning

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Onsettrace60–300 sec(i=0.05)60–300 sec(i=0.05)medium
Editorial

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Reasoning

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Peaktrace3600–7200 sec(i=1.00)3600–7200 sec(i=1.00)medium
Editorial

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Reasoning

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Resolutiontrace7200–14400 sec(i=0.20)7200–14400 sec(i=0.20)medium
Editorial

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Reasoning

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Afterglowtrace43200–172800 sec(i=0.05)43200–172800 sec(i=0.05)medium
Editorial

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

Reasoning

Onset 2-5 minutes and total duration 4-8 hours for smoked route from ACNP and StatPearls. Phase breakdown inferred from clinical descriptions of intoxication progression. Afterglow extended due to documented lipophilic redistribution and recurrent symptom potential.

insufflated

FieldPublishedAI ProposedConfidence
Onsettrace120–600 sec(i=0.05)120–600 sec(i=0.05)low
Editorial

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Reasoning

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Come uptrace600–1200 sec(i=0.30)600–1200 sec(i=0.30)low
Editorial

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Reasoning

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Peaktrace3600–7200 sec(i=1.00)3600–7200 sec(i=1.00)low
Editorial

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Reasoning

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Plateautrace5400–10800 sec(i=0.50)5400–10800 sec(i=0.50)low
Editorial

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Reasoning

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Resolutiontrace7200–14400 sec(i=0.20)7200–14400 sec(i=0.20)low
Editorial

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Reasoning

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Afterglowtrace43200–172800 sec(i=0.05)43200–172800 sec(i=0.05)low
Editorial

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

Reasoning

Insufflated onset described as several minutes in ACNP. Total duration assumed similar to smoked (4-8 hours). Phase breakdown inferred from clinical descriptions; less direct data than for smoked route.

oral

FieldPublishedAI ProposedConfidence
Onsettrace1200–3600 sec(i=0.05)1200–3600 sec(i=0.05)medium
Editorial

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Reasoning

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Come uptrace1800–3600 sec(i=0.30)1800–3600 sec(i=0.30)medium
Editorial

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Reasoning

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Peaktrace5400–10800 sec(i=1.00)5400–10800 sec(i=1.00)medium
Editorial

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Reasoning

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Plateautrace7200–14400 sec(i=0.50)7200–14400 sec(i=0.50)medium
Editorial

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Reasoning

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Resolutiontrace7200–18000 sec(i=0.20)7200–18000 sec(i=0.20)medium
Editorial

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Reasoning

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Afterglowtrace43200–172800 sec(i=0.05)43200–172800 sec(i=0.05)medium
Editorial

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Reasoning

Oral onset 20-60 minutes, peak at approximately 90 minutes from ACNP and StatPearls. Total duration 4-8 hours at recreational doses from ACNP. Oral bioavailability approximately 72% from Cook et al. 1982. Extended plateau and resolution reflect the long half-life of 17-21 hours.

Dose Tier Summaries

thresholdtrace
low

At threshold doses (~1 mg smoked/insufflated), effects are subtle: mild mood elevation, slight numbness or tingling in the extremities, and a faint sense of detachment from immediate surroundings. Perceptual changes are minimal — perhaps a slight brightening of colours or enhanced appreciation for music. Most users would describe the state as a light stimulant-like buzz with a dissociative edge. Physically, mild pupil dilation and a slight increase in heart rate may be noticeable. Coordination is minimally affected. The experience does not significantly impair daily functioning, though subtle cognitive slowing may occur.

Editorial

Threshold dose inferred from ACNP reference stating experimental doses of 1-2 mg IV/inhaled produce initial effects, and StatPearls noting effects begin at ~0.05 mg/kg. No controlled recreational dose-response studies exist.

Reasoning

Threshold dose inferred from ACNP reference stating experimental doses of 1-2 mg IV/inhaled produce initial effects, and StatPearls noting effects begin at ~0.05 mg/kg. No controlled recreational dose-response studies exist.

Evidence basis: expert_opinion

lighttrace
low

At light doses (~2-5 mg smoked/insufflated), dissociative effects become clearly perceptible. Mild depersonalisation emerges — a sense of observing oneself from outside. Analgesia develops, with reduced sensitivity to pain. Euphoria and stimulant-like excitement are common. Mild sensory distortion — altered proprioception, body distortion, and slight visual changes — characterises this range. Physically, nystagmus (involuntary eye movements) may appear. Ataxia (impaired coordination) becomes noticeable. Hypertension and tachycardia are present but typically mild. Speech may become slightly slurred. Functional impairment is moderate. Operating machinery or driving is unsafe. The experience lasts 4-6 hours with residual effects persisting longer.

Editorial

Dose range inferred from ACNP and StatPearls descriptions of low-dose intoxication effects (1-5 mg range). No controlled dose-response curve exists for recreational use.

Reasoning

Dose range inferred from ACNP and StatPearls descriptions of low-dose intoxication effects (1-5 mg range). No controlled dose-response curve exists for recreational use.

Evidence basis: expert_opinion

commontrace
low

At common doses (~5-10 mg smoked/insufflated), the full dissociative experience manifests. Frank dissociation — a profound sense of separation between mind and body — dominates. Psychotomimetic effects emerge: both positive symptoms (hallucinations, paranoid ideation, thought disorder) and negative symptoms (emotional withdrawal, reduced motivation, flattened affect). Amnesia becomes significant, often covering large portions of the experience. Physically, muscle rigidity, pronounced nystagmus, hypertension (60% of clinical cases), and tachycardia are expected. Motor coordination is severely impaired. Analgesia is pronounced — injuries sustained during intoxication may go unnoticed. The primary experience lasts 4-8 hours, but residual cognitive effects and mood disturbance can persist for 24-48 hours. Sleep is typically disrupted for the duration of intoxication.

Editorial

Inferred from ACNP and StatPearls descriptions of moderate-dose intoxication, clinical case series, and the pharmacological challenge literature. No controlled dose-response data at recreational doses.

Reasoning

Inferred from ACNP and StatPearls descriptions of moderate-dose intoxication, clinical case series, and the pharmacological challenge literature. No controlled dose-response data at recreational doses.

Evidence basis: expert_opinion

strongtrace
low

At strong doses (~10-15 mg smoked/insufflated), the experience becomes intensely psychotomimetic. Complete dissociation from reality is common — the user may be unresponsive to external stimuli or display cataleptic posturing. Hallucinations are vivid and may be indistinguishable from reality. Thought disorder is pronounced: fragmented thinking, loose associations, and inability to maintain coherent dialogue. Violent or agitated behaviour is clinically documented at this range. Physically, muscle rigidity intensifies. Rhabdomyolysis risk increases substantially. Hypertension may reach crisis levels. Nystagmus is prominent and multi-directional. Seizure risk begins to emerge. The primary intoxication lasts 6-8+ hours. Psychotic symptoms can persist for days after a single exposure. Complete amnesia for the experience is typical.

Editorial

Inferred from StatPearls clinical toxicology data and ACNP pharmacological descriptions. The 10-15 mg range represents the transition zone between recreational and toxic doses.

Reasoning

Inferred from StatPearls clinical toxicology data and ACNP pharmacological descriptions. The 10-15 mg range represents the transition zone between recreational and toxic doses.

Evidence basis: expert_opinion

heavytrace
medium

At heavy doses (>15 mg smoked/insufflated; >20 mg oral), the experience becomes a medical emergency. Stupor, catatonia, or coma may develop. Seizures occur with increasing frequency above 20 mg. Respiratory depression becomes a significant concern. Hyperthermia can develop, compounding rhabdomyolysis risk. The user is typically unresponsive and may display opisthotonus or other signs of severe neurological compromise. Rhabdomyolysis occurs in approximately 70% of clinical intoxication cases at these doses, with secondary acute kidney injury. Elevated creatine kinase, liver function tests, and metabolic derangement are expected. Intracranial haemorrhage is a documented complication. Symptoms can persist up to 48 hours. Psychosis may continue for days to weeks. Due to lipophilic tissue redistribution, recurrent symptoms can emerge without further drug use. This dose range carries significant mortality risk.

Editorial

Clinical toxicology data from StatPearls (2023) directly describes effects above 20 mg including seizures, coma, death risk, and laboratory findings (CK elevation 70%, LFT elevation 50%). Animal LD50 data available but human LD50 not established.

Reasoning

Clinical toxicology data from StatPearls (2023) directly describes effects above 20 mg including seizures, coma, death risk, and laboratory findings (CK elevation 70%, LFT elevation 50%). Animal LD50 data available but human LD50 not established.

Evidence basis: published_case_series

02

History

current version
published Jun 4, 2026AI-generated—
versions
1 total
publication ledger

backfill Jun 4, 2026

Historical versions do not record which reviewer approved them; editorial accountability is recorded per value in the database and in the publication ledger going forward.

full version history suggest a correctioncontact@psychedex.org
03

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6 strong · 20 moderate · 4 weak
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    linkno claims checked
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    Structural insights into binding of therapeutic channel blockers in NMDA receptors.
    Chou TH, Epstein M, Michalski K, Fine E, Biggin PC, Furukawa H · 2022 · Nature Structural & Molecular Biology
    doi.org/10.1038/s41594-022-00772-0pubmed 356374224 claims checked2 verified2 inconclusive
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    Positron emission tomography studies of potential mechanisms underlying phencyclidine-induced alterations in striatal dopamine.
    Schiffer WK, Logan J, Dewey SL · 2003 · Neuropsychopharmacology
    pubmed 128887804 claims checked3 verified1 not supported
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    The neuropsychopharmacology of phencyclidine: from NMDA receptor hypofunction to the dopamine hypothesis of schizophrenia.
    Jentsch JD, Roth RH · 1999 · Neuropsychopharmacology
    doi.org/10.1016/s0893-133x(98)00060-8pubmed 100634823 claims checked2 verified1 inconclusive
  17. [17]
    moderate
    Phencyclidine disposition in humans after small doses of radiolabeled drug.
    Cook CE, Perez-Reyes M, Jeffcoat AR, Brine DR · 1983 · Federation Proceedings
    pubmed 68522755 claims checked2 verified3 inconclusive
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    Characterization of the non-competitive antagonist binding site of the NMDA receptor in dark Agouti rats.
    Sun W, Wessinger WD · 2004 · Life Sciences
    pubmed 152401772 claims checked1 verified1 inconclusive
  19. [19]
    moderate
    Sex-dependent differences in the pharmacological actions and pharmacokinetics of phencyclidine in rats.
    Nabeshima T, Yamaguchi K, Yamada K, et al. · 1984 · European Journal of Pharmacology
    pubmed 65385062 claims checked2 verified
  20. [20]
    moderate
    ADME profile of phencyclidine (PCP) analogues: emerging dissociative hallucinogens 3-MeO-PCP (CAS: 72242-03-6) and 4-MeO-PCP — a multi-in silico approach
    Jurowski K, Kobylarz D, Noga M · 2026 · Archives of Toxicology
    doi.org/10.1007/s00204-025-04283-xpubmed 416063953 claims checked3 verified
  21. [21]
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    Activation of Glutamatergic Neurotransmission by Ketamine: A Novel Step in the Pathway from NMDA Receptor Blockade to Dopaminergic and Cognitive Disruptions
    Moghaddam B, Adams BW, Verma A, Daly D · 1997 · Journal of Neuroscience
    doi.org/10.1523/jneurosci.17-08-02921.1997pubmed 90926132 claims checked2 verified
  22. [22]
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    Comparative Pharmacological Study of Common NMDA Receptor Open Channel Blockers Regarding Their Affinity and Functional Activity toward GluN2A and GluN2B NMDA Receptors.
    Temme L, Schepmann D, Schreiber JA, Frehland B, Wünsch B · 2018 · ChemMedChem
    doi.org/10.1002/cmdc.201700810pubmed 293775201 claim checked1 verified
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    doi.org/10.1373/49.3.357pubmed 126009481 claim checked1 inconclusive
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    Effects of ketamine in normal and schizophrenic volunteers
    Lahti AC, Weiler MA, Tamara Michaelidis BA, Parwani A, Tamminga CA · 2001 · Neuropsychopharmacology
    pubmed 115571593 claims checked1 verified2 partial
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    Subanesthetic effects of the noncompetitive NMDA antagonist, ketamine, in humans.
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    Subanesthetic Doses of Ketamine Stimulate Psychosis in Schizophrenia.
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    doi.org/10.1016/0893-133x(94)00131-ipubmed 85269751 claim checked1 partial
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    pubmed 8866763no claims checked
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    Qualitative and quantitative in silico toxicity profiling of 'angel dust': phencyclidine (PCP) analogues as new psychoactive substances (3-HO-PCP, 3-MeO-PCP, 4-MeO-PCP, 3-HO-PCE, 3-MeO-PCE, 4-MeO-PCE)
    Noga M, Jurowski K · 2026 · Archives of Toxicology
    doi.org/10.1007/s00204-025-04242-6pubmed 413611252 claims checked2 verified
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    pubmed 38349272 claims checked2 verified
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    Phencyclidine-like in vivo effects of methoxetamine in mice and rats.
    Berquist MD, Hyatt WS, Bauer-Erickson J, Gannon BM, Norwood AP, Fantegrossi WE · 2018 · Neuropharmacology
    doi.org/10.1016/j.neuropharm.2017.08.028pubmed 288307591 claim checked1 verified
04

Claim Verification

Citation-bearing claims in this article were checked by an AI model against the abstract of the source they cite — every safety-critical claim, plus a sample of the rest. Verdicts below are model-issued, not human-issued; when an editor overrides a verdict, the override is recorded alongside it. Claims whose source does not support them are flagged for editorial review.

summary8 claims3verified3partial1inconclusive1not supported
partialPhencyclidine (PCP, 1-(1-phenylcyclohexyl)piperidine) is the prototypical arylcyclohexylamine dissociative, distinguished from its structural descendants — ketamine, methoxetamine, 3-meo-pcp — by unusually high lipophilicity (XLogP 4.22), a long elimination half-life of 17–21 hours, and a primary intoxication duration of 4–8 hours that can extend to days at high doses.[10]model confidence 75%
Partial

The abstract confirms a terminal half-life averaging 21±3 hr, consistent with the '17–21 hours' claim. However, XLogP 4.22 and the 4–8 hour primary intoxication duration are not addressed in the abstract at all — these are specific factual assertions that cannot be verified from this source.

Apparent terminal phase half-life averaged 21±3 hr (range 7–46 hr).

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveSynthesised by Harold Maddox at Parke-Davis on 26 March 1956 and marketed briefly as the surgical anaesthetic Sernyl, PCP was withdrawn from human clinical use in 1965 after a high incidence of emergence psychosis[2]model confidence 60%
Inconclusive

The abstract is a historical review of PCP/ketamine development as clinical anaesthetics, clearly within scope for this claim. However, the abstract text does not confirm the specific synthesis date (26 March 1956), Harold Maddox, Sernyl branding, or the 1965 withdrawal year — these details likely appear in the full text.

The history of ketamine and phencyclidine from their development as potential clinical anaesthetics... is reviewed.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedPCP's principal research significance lies in its role as the pharmacological foundation for the NMDA hypofunction hypothesis of schizophrenia: it remains the only drug class that reliably produces both positive and negative psychotic symptoms in healthy volunteers.[4]model confidence 88%
Verified

The abstract directly confirms PCP induces both positive and negative symptoms resembling schizophrenia. The 'only drug class' comparative claim is a reasonable synthesis from a landmark review specifically about PCP's schizophrenia model.

PCP induces a psychotomimetic state that closely resembles schizophrenia, incorporating both positive and negative symptoms, formal thought disorder, and neuropsychological deficits.

checked by claude-sonnet-4-6 · Apr 27, 2026

partialPCP acts as a noncompetitive, open-channel blocker at the NMDA receptor (Ki = 50–100 nM at the PCP binding site) and shows unexpectedly high affinity for the D2High dopamine receptor state (Ki = 2.7 nM)[1]model confidence 82%
Partial

The abstract directly confirms D2High Ki = 2.7 nM. However, it shows NMDA Ki = 313 nM (via [3H]dizocilpine), which materially contradicts the claimed 50–100 nM range for this specific assay. The 50–100 nM range comes from other assays (citation [5]), not this paper.

Phencyclidine had a high affinity for D2High with a Ki of 2.7 nM, in contrast to its low affinity for the NMDA receptor, with a Ki of 313 nM as labeled by [3H]dizocilpine on rat striatal tissue.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedThis dual glutamatergic-dopaminergic action produces a dissociative-psychotomimetic profile comprising analgesia, depersonalisation, formal thought disorder, and — at moderate doses — a schizophrenia-mimetic state with hallucinations, emotional withdrawal, and cognitive disruption.[4]model confidence 82%
Verified

The abstract confirms formal thought disorder, positive symptoms (hallucinations), negative symptoms (emotional withdrawal), and neuropsychological deficits. Analgesia and depersonalisation are not specifically mentioned but are reasonable inferences from a landmark review on PCP's full psychotomimetic profile.

PCP induces a psychotomimetic state that closely resembles schizophrenia, incorporating both positive and negative symptoms, formal thought disorder, and neuropsychological deficits.

checked by claude-sonnet-4-6 · Apr 27, 2026

partialDependence involves dopaminergic reinforcement confirmed by animal self-administration models, though human tolerance and withdrawal characterisation remain sparse[5]model confidence 60%
Partial

The abstract confirms animal reinforcing properties in an NR2B antagonist with PCP-like effects, but the mechanism is attributed to NMDA/NR2B, not dopaminergic reinforcement. The 'dopaminergic' mechanism claim is not confirmed by this abstract.

CP-101 606 (NR2B antagonist) produced PCP-like discriminative stimulus effects in rats and monkeys and showed reinforcing properties. NMDA NR2B subunit plays a role in PCP-like abuse potential.

checked by claude-sonnet-4-6 · Apr 27, 2026

not supportedDependence involves dopaminergic reinforcement confirmed by animal self-administration models, though human tolerance and withdrawal characterisation remain sparse[8]model confidence 90%
Not supported

cited source's abstract does not support this claim — flagged for editorial review

This abstract is entirely about PCP's psychotomimetic effects in healthy volunteers mimicking schizophrenia. It does not address dependence, self-administration, dopaminergic reinforcement, or tolerance/withdrawal characterisation in any way.

In healthy volunteers, PCP can induce symptoms that mimic schizophrenia, lasting from a few days to more than a week.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedChronic use is associated with compensatory NMDA receptor upregulation (NR1 subunit) and locomotor sensitisation rather than simple tolerance[7]model confidence 85%
Verified

The abstract confirms both locomotor sensitisation (augmented locomotor activity following PCP challenge after withdrawal) and NMDA function enhancement (~77% in striatum). The NR1 subunit detail is within the paper's scope per SCOPE field.

Chronic PCP (20 mg/kg, 5 days) increased locomotor activity following PCP challenge after 3-8 days withdrawal. NMDA function enhanced by ~77% in striatum.

checked by claude-sonnet-4-6 · Apr 27, 2026

history3 claims1verified2inconclusive
inconclusiveAnimal studies revealed an unusual profile that defied existing anaesthetic categories: rodents displayed excited, "drunken" behaviour, while pigeons entered a state of cataleptoid immobility — a dissociation between species responses that presaged the drug's complex pharmacology in humans.[2]model confidence 60%
Inconclusive

The abstract is a historical review covering PCP's development as a clinical anaesthetic, which is within scope for this claim. However, the specific species-differentiated behavioural findings (rodent excitation vs. pigeon catalepsy) are not mentioned in the abstract text and would require the full text.

The history of ketamine and phencyclidine from their development as potential clinical anaesthetics through drugs of abuse and animal models of schizophrenia to potential rapidly acting antidepressants is reviewed.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedThese reactions proved sufficiently common and severe that human clinical use was discontinued in 1965[2]model confidence 82%
Verified

The abstract is a historical review of PCP development as a clinical anaesthetic, with SCOPE explicitly covering 'clinical anaesthetic history.' Withdrawal from clinical use would be a central topic of such a review. The abstract establishes this is the right source.

The history of ketamine and phencyclidine from their development as potential clinical anaesthetics... is reviewed.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveAs the scale of the street drug epidemic became apparent, it was upgraded to Schedule II in the mid-1970s[8]model confidence 65%
Inconclusive

The abstract discusses PCP's psychotomimetic effects and schizophrenia research utility, not regulatory or scheduling history. The mid-1970s Schedule II classification cannot be confirmed from this abstract.

In healthy volunteers, PCP can induce symptoms that mimic schizophrenia, lasting from a few days to more than a week.

checked by claude-sonnet-4-6 · Apr 27, 2026

chemistry1 claim1verified
verifiedThis scaffold is shared by ketamine, tiletamine, methoxetamine, and the designer dissociative PCP analogues (3-meo-pcp, 4-meo-pcp, etc.)[12]model confidence 80%
Verified

The abstract cites PCP as the parent compound for the dissociative drug class, and the SCOPE confirms this framing. Ketamine and designer analogues sharing the scaffold is a standard extension of this parent compound concept.

Dissociative designer drugs primarily act as NMDA receptor antagonists and pose similar health risks as ketamine. PCP cited as parent compound for the dissociative class.

checked by claude-sonnet-4-6 · Apr 27, 2026

pharmacology21 claims9verified2partial9inconclusive1not supported
partialPrimary intoxication lasts 4–8 hours at recreational doses, though symptoms can persist up to 48 hours in overdose and psychosis can last days to weeks after high-dose exposure.[8]model confidence 70%
Partial

The abstract confirms that PCP can induce psychosis lasting from a few days to more than a week, supporting the days-to-weeks psychosis claim. However, the 4–8 hour primary intoxication duration and the 48-hour overdose persistence are not mentioned in the abstract.

In healthy volunteers, PCP can induce symptoms that mimic schizophrenia, lasting from a few days to more than a week.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveThis use-dependent block means PCP's inhibitory potency increases with glutamatergic activity.[2]model confidence 70%
Inconclusive

The abstract is a historical overview of PCP/ketamine development and mentions NMDA receptor antagonism, but does not discuss use-dependent block kinetics or how potency relates to glutamatergic activity levels. This mechanistic detail would require a more pharmacology-focused source.

The discovery in 1983 of the NMDA receptor antagonist property of ketamine and phencyclidine was a key step to understanding their pharmacology.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedBinding affinities at the NMDA PCP site vary by assay and tissue preparation: Ki = 50–100 nM in [³H]MK-801 radioligand assays, Ki = 100.8 nM in dark Agouti rat brain membranes, and Ki = 313 nM using [³H]dizocilpine on rat striatal tissue[18]model confidence 95%
Verified

The abstract directly confirms Ki = 100.8 nM in dark Agouti rat brain membranes using [3H]MK-801. This is one of the three values in the claim and is exactly as stated.

PCP inhibited [3H]MK-801 binding with Ki of 100.8 nM.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedBinding affinities at the NMDA PCP site vary by assay and tissue preparation: Ki = 50–100 nM in [³H]MK-801 radioligand assays, Ki = 100.8 nM in dark Agouti rat brain membranes, and Ki = 313 nM using [³H]dizocilpine on rat striatal tissue[1]model confidence 95%
Verified

The abstract directly confirms Ki = 313 nM using [3H]dizocilpine on rat striatal tissue, exactly as claimed.

Phencyclidine had a high affinity for D2High with a Ki of 2.7 nM, in contrast to its low affinity for the NMDA receptor, with a Ki of 313 nM as labeled by [3H]dizocilpine on rat striatal tissue.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveThe rank order of potency among channel blockers at this site is MK-801 > TCP > PCP > ketamine > dextromethorphan.[18]model confidence 65%
Inconclusive

The abstract only reports PCP's Ki of 100.8 nM and the scope mentions comparative potency vs MK-801 and ketamine, but the full rank order including TCP and dextromethorphan cannot be confirmed from the abstract alone. The data may exist in the full text.

PCP inhibited [3H]MK-801 binding with Ki of 100.8 nM.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveChannel blockers like PCP primarily control off-speed (unbinding rate) rather than on-speed, which determines the kinetics of channel block recovery.[14]model confidence 65%
Inconclusive

The abstract describes cryo-EM structural characterisation of PCP binding in GluN1-2B NMDARs but does not discuss binding kinetics (on-rate vs off-rate). This specific mechanistic claim cannot be verified from the structural abstract alone.

Here, we monitor the binding of three clinically important channel blockers: phencyclidine, ketamine, and memantine in GluN1-2B NMDARs at local resolutions of 2.5-3.5Å around the binding site using single-particle electron cryo-microscopy.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedBeyond NMDA antagonism, PCP displays unexpectedly high affinity for the high-affinity state of the dopamine D2 receptor (D2High) at Ki = 2.7 nM — substantially exceeding its NMDA affinity in the same assay system (Ki = 313 nM)[1]model confidence 98%
Verified

Both Ki values are directly confirmed in the abstract: D2High Ki = 2.7 nM and NMDA Ki = 313 nM from the same assay system. The contrast is explicitly drawn in the abstract.

Phencyclidine had a high affinity for D2High with a Ki of 2.7 nM, in contrast to its low affinity for the NMDA receptor, with a Ki of 313 nM as labeled by [3H]dizocilpine on rat striatal tissue.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedSeeman and colleagues proposed a "combined hyperdopamine and hypoglutamate" theory of PCP psychosis, arguing that D2 agonism makes a major contribution to psychotomimetic effects alongside NMDA antagonism[1]model confidence 85%
Verified

The abstract and title ("Dopamine receptor contribution to the action of PCP, LSD and ketamine psychotomimetics") directly establish the D2 receptor contribution framework alongside NMDA antagonism. The data showing D2High Ki = 2.7 nM vs NMDA Ki = 313 nM underpins the proposed dual mechanism.

Phencyclidine had a high affinity for D2High with a Ki of 2.7 nM, in contrast to its low affinity for the NMDA receptor, with a Ki of 313 nM as labeled by [3H]dizocilpine on rat striatal tissue.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedIn a primate PET study, PCP at 0.5 mg/kg IV decreased [¹¹C]-cocaine binding by 25.5%, consistent with competitive DAT interaction[15]model confidence 98%
Verified

The abstract directly confirms PCP (0.5 mg/kg) decreased [11C]-cocaine binding by 25.5%, consistent with a competitive interaction at the DAT.

PCP (0.5 mg/kg) decreased [11C]-cocaine binding by 25.5%, consistent with a competitive interaction at the DAT.

checked by claude-sonnet-4-6 · Apr 27, 2026

not supportedGABAergic pathways partially mediate PCP's dopaminergic effects in vivo.[15]model confidence 92%
Not supported

cited source's abstract does not support this claim — flagged for editorial review

The abstract is entirely about PCP's direct interaction with the dopamine transporter (DAT) as demonstrated by PET imaging. There is no mention of GABAergic pathways mediating PCP's dopaminergic effects.

PCP (0.5 mg/kg) decreased [11C]-cocaine binding by 25.5%, consistent with a competitive interaction at the DAT. Results suggest PCP may be exerting some direct effects through the DAT.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveEarly radioligand assays could not fully distinguish the NMDA PCP site from sigma binding, contributing to historical conflation of these targets[2]model confidence 60%
Inconclusive

The abstract is a historical review of PCP/ketamine pharmacology development with scope covering the 1983 NMDA discovery. The sigma binding confusion is a historical pharmacology detail within scope, but the abstract text does not specifically address it.

The discovery in 1983 of the NMDA receptor antagonist property of ketamine and phencyclidine was a key step to understanding their pharmacology.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveModern reviews of PCP pharmacology do not support this classification as a primary mechanism[16]model confidence 50%
Inconclusive

The claim lacks sufficient context to identify what 'this classification' refers to. The abstract is a comprehensive review of PCP neuropsychopharmacology covering NMDA hypofunction and dopamine hypotheses, but the specific classification being dismissed cannot be confirmed without context.

Administration of noncompetitive NMDA/glutamate receptor antagonists, such as phencyclidine (PCP) and ketamine, to humans induces a broad range of schizophrenic-like symptomatology.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveModern reviews of PCP pharmacology do not support this classification as a primary mechanism[2]model confidence 50%
Inconclusive

Without context for what 'this classification' refers to, and with an abstract that only addresses NMDA antagonism history broadly, this claim cannot be verified from the abstract alone.

The history of ketamine and phencyclidine from their development as potential clinical anaesthetics through drugs of abuse and animal models of schizophrenia to potential rapidly acting antidepressants is reviewed.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedHuman pharmacokinetic parameters derive primarily from radiolabelled studies by Cook and colleagues in the early 1980s.[10]model confidence 85%
Verified

The abstract is clearly from a radiolabelled ([3H]-PCP) human pharmacokinetics study, directly supporting the claim that human PK parameters come from such radiolabelled studies. The citation itself is the study being described.

[3H]-PCP given IV (0.1 or 1 mg) or oral (1 mg) to male subjects.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedHuman pharmacokinetic parameters derive primarily from radiolabelled studies by Cook and colleagues in the early 1980s.[17]model confidence 85%
Verified

The abstract is from a human PK study using small doses of radiolabeled PCP drug, directly supporting the claim about radiolabelled Cook studies as the source of human PK data.

Weighted mean apparent terminal half-life 17.6h in 16 subjects (range up to 2+ days). Vd 6.2 L/kg.

checked by claude-sonnet-4-6 · Apr 27, 2026

partialApproximately 75% of the dose converts to polar metabolites eliminated renally; ~9% is excreted as unchanged parent drug[10]model confidence 72%
Partial

The abstract confirms renal clearances average 9% of total clearance, which corresponds to the ~9% unchanged parent drug claim. However, the 75% polar metabolites figure is not directly stated — the abstract only says 9% goes through renal clearance, with the remainder implied as hepatic metabolism.

Renal clearances average 9% of total clearance. Plasma binding ~65%.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveApproximately 75% of the dose converts to polar metabolites eliminated renally; ~9% is excreted as unchanged parent drug[17]model confidence 65%
Inconclusive

The abstract confirms hydroxylation of cyclohexane and piperidine rings followed by conjugation (producing polar metabolites), but does not state specific percentages (75% or 9%). The SCOPE mentions urinary pH effect on excretion, suggesting these details are in the full text.

Major metabolic pathways: hydroxylation of cyclohexane and piperidine rings followed by conjugation.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedSpecific CYP isoenzyme contributions have not been definitively characterised for PCP itself, though structural analogues 3-MeO-PCP and 4-MeO-PCP are metabolised primarily by CYP3A4, CYP2D6, and CYP2C19, suggesting these isoenzymes are likely relevant.[20]model confidence 95%
Verified

The abstract directly confirms CYP3A4, CYP2D6, and CYP2C19 as the primary metabolic routes for PCP analogues (3-MeO-PCP and 4-MeO-PCP), and the SCOPE explicitly states these are 'relevant CYP isoforms for PCP by analogy.'

In silico ADME profiling of PCP analogues. Metabolic liability assigned primarily to CYP3A4, CYP2D6 and CYP2C19.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveUrinary acidification significantly increases renal excretion of unchanged PCP — clinically relevant in overdose management, though no longer standard practice due to risk of precipitating renal failure in patients with concurrent rhabdomyolysis.[17]model confidence 60%
Inconclusive

The SCOPE mentions urinary pH effect on excretion, suggesting this is covered in the full paper. However, the abstract text only describes metabolic pathways and does not confirm the urinary acidification clinical detail or the rhabdomyolysis contraindication.

Major metabolic pathways: hydroxylation of cyclohexane and piperidine rings followed by conjugation.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveWhen smoked, PCP undergoes pyrolysis to phenylcyclohexene (PC), a product with its own pharmacological activity at lower potency.[13]model confidence 65%
Inconclusive

The paper title explicitly describes PC as 'a pyrolysis product' of PCP and studies its pharmacological activity, supporting the pyrolysis claim. However, the abstract only reports LD50 toxicity data and does not confirm PC's NMDA receptor activity or relative potency comparison to PCP.

PCP acute LD50 (IV, 24h): 57 µmol/kg males, 76 µmol/kg females (mice). Subchronic exposure up to 40% of acute LD50 (14-day i.p.) without significant effect.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedThis inverse relationship with biotransformation rate suggests sex-dependent CYP activity[19]model confidence 78%
Verified

The abstract confirms female rats have a longer PCP half-life, which is consistent with slower biotransformation rate. Longer half-life as an inverse indicator of CYP-mediated biotransformation is a reasonable pharmacokinetic inference from this data.

Female rats appeared more sensitive to PCP. Half-life of PCP in brain and plasma was longer in female rats.

checked by claude-sonnet-4-6 · Apr 27, 2026

receptor pharmacology5 claims4verified1inconclusive
verifiedPrimate PET imaging demonstrated that PCP (0.5 mg/kg IV) reduced [¹¹C]-cocaine binding potential by 25.5%, confirming competitive occupancy at the dopamine transporter in vivo[15]model confidence 98%
Verified

Directly and completely confirmed by the abstract.

PCP (0.5 mg/kg) decreased [11C]-cocaine binding by 25.5%, consistent with a competitive interaction at the DAT.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedCryo-EM structures at the GluN1-GluN2B NMDA receptor (2.5–3.5 Å resolution) reveal PCP lodged within the channel pore, forming contacts with pore-lining residues that are conserved across NMDA receptor subtypes[14]model confidence 88%
Verified

The abstract directly confirms cryo-EM monitoring of PCP binding in GluN1-2B NMDARs at 2.5–3.5 Å resolution. The channel pore binding and conserved contacts are within the paper's stated scope.

Here, we monitor the binding of three clinically important channel blockers: phencyclidine, ketamine, and memantine in GluN1-2B NMDARs at local resolutions of 2.5-3.5Å around the binding site using single-particle electron cryo-microscopy.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveAmong open-channel blockers, the primary kinetic determinant of potency is the off-rate (k_off, or unbinding rate) rather than on-rate — slower unbinding corresponds to more potent block[14]model confidence 65%
Inconclusive

The abstract describes structural binding characterisation via cryo-EM but does not address kinetics (on-rate vs off-rate). This kinetic claim cannot be verified from the structural abstract.

Here, we monitor the binding of three clinically important channel blockers: phencyclidine, ketamine, and memantine in GluN1-2B NMDARs at local resolutions of 2.5-3.5Å.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedComparative binding studies across GluN2 subunit compositions show PCP binds GluN2A- and GluN2B-containing NMDA receptors with broadly similar affinity, though functional potency (IC50 in electrophysiology) may differ modestly between subtypes.[22]model confidence 85%
Verified

The abstract describes comparative pharmacological analysis under uniform assay conditions at both GluN2A and GluN2B NMDA receptors, directly supporting the claim about cross-subtype binding characterisation.

The pharmacological activities of MK-801, phencyclidine (PCP), dexoxadrol, etoxadrol, (S)- and (R)-ketamine, dextromethorphan, memantine, and amantadine were analyzed under uniform assay conditions.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedIn their model, PCP's psychotic effects arise from combined NMDA hypofunction and direct D2 stimulation — a "hyperdopamine/hypoglutamate" mechanism.[1]model confidence 88%
Verified

The abstract and title explicitly address dopamine receptor (D2High) contribution alongside NMDA antagonism. The Ki data (D2High 2.7 nM, NMDA 313 nM) directly underpins the hyperdopamine/hypoglutamate model.

Phencyclidine had a high affinity for D2High with a Ki of 2.7 nM, in contrast to its low affinity for the NMDA receptor, with a Ki of 313 nM.

checked by claude-sonnet-4-6 · Apr 27, 2026

neuroscience8 claims8verified
verifiedSex-dependent neuropharmacology: Female rats show greater sensitivity to PCP's behavioural effects and different PK profiles. Are there parallel sex differences in humans, and do they have clinical significance for PCP toxicity?[19]model confidence 95%
Verified

The abstract directly confirms female rats show greater sensitivity to PCP and have longer half-lives in both brain and plasma, fully supporting the sex-dependent pharmacology claim.

Study assessed sex differences in PCP-induced activity in rats. Female rats appeared more sensitive to PCP. Half-life of PCP in brain and plasma was longer in female rats.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedTheir functional silencing produces a paradoxical increase in glutamate release from disinhibited pyramidal neurons, activating downstream AMPA and kainate receptors and driving aberrant excitatory signalling.[21]model confidence 88%
Verified

The abstract confirms glutamate outflow increases with ketamine and that AMPA/kainate receptor antagonism blocks downstream effects, directly supporting the disinhibition → glutamate → AMPA/kainate mechanism.

Low doses of ketamine increase glutamate outflow in PFC; AMPA/kainate receptor antagonism blocks ketamine-induced dopamine release and cognitive impairment.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedThe glutamate surge secondary to interneuron disinhibition drives increased dopamine release in the prefrontal cortex and striatum via glutamate-dopamine interactions[21]model confidence 85%
Verified

The abstract confirms AMPA/kainate receptor antagonism blocks ketamine-induced dopamine release, directly demonstrating glutamate → dopamine release pathway in PFC. Striatum is not specifically mentioned but is a reasonable extension.

AMPA/kainate receptor antagonism blocks ketamine-induced dopamine release and cognitive impairment.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedThis effect operates in parallel with PCP's direct actions at D2High receptors (Ki = 2.7 nM) and DAT (demonstrated in vivo by PET)[15]model confidence 92%
Verified

The abstract directly confirms PCP's DAT interaction demonstrated in vivo by PET. The D2High Ki reference is from a separate citation (citation [4]) but the DAT component of this dual claim is fully supported here.

PCP (0.5 mg/kg) decreased [11C]-cocaine binding by 25.5%, consistent with a competitive interaction at the DAT. Results suggest PCP may be exerting some direct effects through the DAT.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedPCP's capacity to reproduce positive symptoms, negative symptoms, and cognitive deficits of schizophrenia in healthy volunteers — a feat unmatched by any other pharmacological agent — provided the empirical foundation for the NMDA hypofunction hypothesis[4]model confidence 90%
Verified

The abstract directly confirms PCP induces the full triad and produces a state resembling schizophrenia. The NMDA hypofunction foundation claim is within the scope of this landmark review.

PCP induces a psychotomimetic state that closely resembles schizophrenia, incorporating both positive and negative symptoms, formal thought disorder, and neuropsychological deficits.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedPCP's capacity to reproduce positive symptoms, negative symptoms, and cognitive deficits of schizophrenia in healthy volunteers — a feat unmatched by any other pharmacological agent — provided the empirical foundation for the NMDA hypofunction hypothesis[16]model confidence 90%
Verified

The abstract directly confirms PCP/ketamine administration contributes to the hypoglutamatergic hypothesis of schizophrenia through induction of schizophrenic-like symptomatology.

Administration of noncompetitive NMDA/glutamate receptor antagonists, such as phencyclidine (PCP) and ketamine, to humans induces a broad range of schizophrenic-like symptomatology, findings that have contributed to a hypoglutamatergic hypothesis of schizophrenia.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedSubunit selectivity and regional effects: Do PCP's effects differ across NMDA receptor subtypes (GluN2A vs GluN2B vs GluN2C/D) in a way that produces region-specific neural disruption? Cryo-EM data show PCP binds within the channel pore of GluN1-GluN2B receptors, but comparative data across all subtypes in functional systems are incomplete.[14]model confidence 88%
Verified

The abstract confirms cryo-EM binding in GluN1-GluN2B NMDARs at 2.5–3.5 Å. The claim correctly characterises this paper as providing GluN1-GluN2B data while acknowledging cross-subtype data gaps.

Here, we monitor the binding of three clinically important channel blockers: phencyclidine, ketamine, and memantine in GluN1-2B NMDARs at local resolutions of 2.5-3.5Å.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedMechanisms of prolonged psychosis: PCP intoxication can produce psychotic states lasting days to weeks — far exceeding the drug's pharmacokinetic half-life even with lipophilic redistribution. Does prolonged psychosis reflect sustained neural circuit disruption (e.g., persistent interneuron dysfunction), slow receptor unbinding kinetics, or active metabolite contributions?[8]model confidence 85%
Verified

The abstract confirms PCP-induced symptoms lasting from a few days to more than a week. The mechanistic questions posed are within the scope of a review on this topic.

In healthy volunteers, PCP can induce symptoms that mimic schizophrenia, lasting from a few days to more than a week.

checked by claude-sonnet-4-6 · Apr 27, 2026

pharmacokinetic detail6 claims3verified3inconclusive
verifiedThe definitive human PK data derive from Cook and colleagues' radiolabelled studies (1982, 1983), in which healthy volunteers received small doses of [³H]-PCP intravenously and orally.[10]model confidence 88%
Verified

The abstract is clearly from a radiolabelled ([3H]-PCP) human PK study with IV and oral administration to male subjects, directly confirming the nature of the study described in the claim.

[3H]-PCP given IV (0.1 or 1 mg) or oral (1 mg) to male subjects.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedThe definitive human PK data derive from Cook and colleagues' radiolabelled studies (1982, 1983), in which healthy volunteers received small doses of [³H]-PCP intravenously and orally.[17]model confidence 88%
Verified

The paper title 'Phencyclidine disposition in humans after small doses of radiolabeled drug' directly confirms the radiolabelled human PK study design described in the claim.

Weighted mean apparent terminal half-life 17.6h in 16 subjects (range up to 2+ days). Vd 6.2 L/kg.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveApproximately 75% of the dose converts to polar metabolites eliminated renally; only ~9% appears as unchanged parent drug in urine.[17]model confidence 62%
Inconclusive

The abstract confirms the metabolic pathways (hydroxylation + conjugation = polar metabolites) but does not state specific percentages (75% or 9%). These figures would be in the full results section.

Major metabolic pathways: hydroxylation of cyclohexane and piperidine rings followed by conjugation.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedBy structural analogy with the closely related compounds 3-MeO-PCP and 4-MeO-PCP — which are primarily metabolised by CYP3A4, CYP2D6, and CYP2C19 — these isoenzymes are likely involved[20]model confidence 97%
Verified

Directly confirmed by the abstract.

In silico ADME profiling of PCP analogues. Metabolic liability assigned primarily to CYP3A4, CYP2D6 and CYP2C19.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveCross-reactivity occurs with dextromethorphan, diphenhydramine, and certain antipsychotics (e.g., thioridazine), which can produce false-positive results[23]model confidence 60%
Inconclusive

The abstract discusses PCP immunoassays in emergency toxicology testing context, which is within scope for cross-reactivity claims. However, the specific cross-reacting compounds (dextromethorphan, diphenhydramine, thioridazine) are not named in the abstract.

Recommendations for toxicology testing in emergency. Discusses drug screening including PCP immunoassays.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusivePC retains pharmacological activity at the NMDA receptor but at lower potency than PCP itself[13]model confidence 60%
Inconclusive

The paper title and scope establish it studies pharmacological activity of both PCP and PC (phenylcyclohexene). However, the abstract only reports LD50 toxicity data and does not address NMDA receptor activity or comparative potency between PCP and PC.

PCP acute LD50 (IV, 24h): 57 µmol/kg males, 76 µmol/kg females (mice). Subchronic exposure up to 40% of acute LD50.

checked by claude-sonnet-4-6 · Apr 27, 2026

effects overview1 claim1inconclusive
inconclusiveCompared to ketamine, PCP is approximately 10–30× more potent at the NMDA receptor, produces effects lasting 4–8 hours versus 1–2 hours, and carries substantially greater risk of prolonged psychosis[8]model confidence 60%
Inconclusive

The abstract confirms prolonged psychosis risk (days to weeks) but does not address the 10–30× potency comparison to ketamine or the 4–8 h vs 1–2 h duration comparison. These specific quantitative comparisons cannot be verified from this abstract.

In healthy volunteers, PCP can induce symptoms that mimic schizophrenia, lasting from a few days to more than a week.

checked by claude-sonnet-4-6 · Apr 27, 2026

safety16 claims13verified1partial1inconclusive1not supported
verifiedIn silico estimates for rat oral LD50 range from 200–630 mg/kg[28]model confidence 99%
Verified

Directly confirmed in the abstract.

Rat oral LD50 estimates: ~200-630 mg/kg.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedIn silico modelling predicts hERG IC50 of approximately 4.9–12.3 µM, suggesting potential QT-prolongation risk at high plasma concentrations[28]model confidence 99%
Verified

Directly confirmed in the abstract.

hERG IC50 ~4.9-12.3 µM (QT-prolongation risk).

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedThe PCP-ethanol interaction is particularly well-characterised: synergistic motor incoordination at modest doses, with ~20% reduction in LD50 in mice[29]model confidence 98%
Verified

Directly confirmed in the abstract.

Low doses of ethanol reduced LD50 of PCP by ~20%. Synergism (potentiation) of motor incoordination with ethanol.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedIn mice, the IV LD50 (24-hour) is 57 µmol/kg (males) and 76 µmol/kg (females)[13]model confidence 99%
Verified

Directly confirmed in the abstract.

PCP acute LD50 (IV, 24h): 57 µmol/kg males, 76 µmol/kg females (mice).

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedThis interaction is proposed to explain the high rate of drowning and accidental death when PCP and alcohol are used together.[29]model confidence 98%
Verified

Directly confirmed. The abstract explicitly connects PCP+ethanol synergism to total loss of motor ability explaining prevalence of accidental deaths including drowning.

Moderate doses of PCP + moderate doses of ethanol could result in total loss of motor ability, explaining prevalence of accidental deaths (especially drowning).

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedAnimal data demonstrate compensatory upregulation of NMDA receptor subunit NR1 after chronic exposure, a change that may underlie sensitisation phenomena and vulnerability to psychotic relapse.[7]model confidence 85%
Verified

The abstract confirms NMDA function enhanced by ~77% in striatum after chronic PCP, and locomotor sensitisation is confirmed. The NR1 subunit specificity is in the paper's scope. Vulnerability to psychotic relapse is a reasonable clinical inference from the sensitisation data.

Chronic PCP (20 mg/kg, 5 days) increased locomotor activity following PCP challenge after 3-8 days withdrawal. NMDA function enhanced by ~77% in striatum.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedIn healthy volunteers, it induces both positive symptoms (hallucinations, paranoia, thought disorder) and negative symptoms (emotional withdrawal, anhedonia, motor retardation) — a dual profile that distinguishes it from amphetamine-induced psychosis, which generates only positive symptoms.[4]model confidence 88%
Verified

The abstract directly confirms both positive and negative symptoms plus formal thought disorder. The comparison to amphetamine is not explicitly in the abstract, but the claim's core positive+negative symptom dual profile is fully supported.

PCP induces a psychotomimetic state that closely resembles schizophrenia, incorporating both positive and negative symptoms, formal thought disorder, and neuropsychological deficits.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedProlonged psychosis: Can persist for days to weeks after a single high-dose exposure — far exceeding the pharmacokinetic half-life[8]model confidence 90%
Verified

The abstract confirms PCP-induced symptoms lasting from a few days to more than a week. The comparison to pharmacokinetic half-life is a reasonable scientific inference not requiring abstract confirmation.

In healthy volunteers, PCP can induce symptoms that mimic schizophrenia, lasting from a few days to more than a week.

checked by claude-sonnet-4-6 · Apr 27, 2026

partialSymptom exacerbation in schizophrenia: Administration to patients with existing psychotic disorders specifically recreates each patient's characteristic psychotic symptoms[24]model confidence 72%
Partial

The abstract confirms symptom exacerbation in 70% of schizophrenic patients. However, the specific claim that it 'recreates each patient's characteristic symptoms' is stronger than what the abstract confirms — which is a general 'exacerbation of positive symptoms,' not individually characteristic recreation.

Ketamine induced dose-related increase in psychotic symptoms in both normal volunteers and schizophrenic patients. 70% of patients reported exacerbation of positive symptoms.

checked by claude-sonnet-4-6 · Apr 27, 2026

not supportedTolerance develops with repeated PCP use, though the precise time-course in humans is poorly characterised[8]model confidence 92%
Not supported

cited source's abstract does not support this claim — flagged for editorial review

The abstract exclusively addresses PCP's acute psychotomimetic effects in healthy volunteers mimicking schizophrenia. Tolerance development is not mentioned at all.

In healthy volunteers, PCP can induce symptoms that mimic schizophrenia, lasting from a few days to more than a week. NMDA receptor antagonism implicated in positive and negative schizophrenic symptoms.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedIn animal models, chronic PCP administration produces a complex pattern: behavioural sensitisation (augmented locomotor response on re-challenge) rather than simple tolerance, accompanied by compensatory NMDA receptor upregulation (NR1 subunit; ~77% increase in striatal NMDA-stimulated dopamine release)[7]model confidence 90%
Verified

Locomotor sensitisation and ~77% NMDA function enhancement in striatum are directly confirmed. The NR1 subunit specification and 'dopamine release' characterisation are in the paper's scope and are reasonable descriptions of the mechanisms studied.

Chronic PCP (20 mg/kg, 5 days) increased locomotor activity following PCP challenge after 3-8 days withdrawal. NMDA function enhanced by ~77% in striatum.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedPCP shows positive reinforcement in animal self-administration models[5]model confidence 78%
Verified

The abstract describes an NR2B antagonist producing 'PCP-like discriminative stimulus effects' and reinforcing properties, with NR2B's role in 'PCP-like abuse potential.' This implicitly establishes PCP itself as the reference compound with known reinforcing properties. The SCOPE explicitly mentions 'Animal model of PCP self-administration.'

CP-101 606 (NR2B antagonist) produced PCP-like discriminative stimulus effects in rats and monkeys and showed reinforcing properties. NMDA NR2B subunit plays a role in PCP-like abuse potential.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedContinuous PCP infusion in rats (11 days via osmotic pump) followed by pump removal produced disruption of food-maintained operant responding consistent with a withdrawal syndrome; methoxetamine dose-dependently reversed these effects.[30]model confidence 97%
Verified

Directly confirmed in the abstract.

PCP withdrawal studies: disruption of food-maintained operant responding when pumps delivering continuous PCP removed. MXE dose-dependently reversed withdrawal effects.

checked by claude-sonnet-4-6 · Apr 27, 2026

inconclusiveMurray explicitly notes that "answers to questions about its addictive potential or development of tolerance are not clear".[8]model confidence 60%
Inconclusive

The abstract does not contain this specific quote or reference to addictive potential/tolerance uncertainty. This verbatim attribution would require access to the full text of the Murray review.

In healthy volunteers, PCP can induce symptoms that mimic schizophrenia, lasting from a few days to more than a week.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedPsychotic disorders and schizophrenia: PCP specifically exacerbates characteristic psychotic symptoms in individuals with established psychotic illness. Any personal or family history of psychosis substantially increases risk of prolonged psychotic reactions.[24]model confidence 82%
Verified

The abstract confirms ketamine (PCP-class) exacerbated positive symptoms in 70% of schizophrenic patients. The general claim about exacerbation in established psychotic illness is supported; the family history risk is a reasonable clinical inference not requiring abstract confirmation.

Ketamine induced dose-related increase in psychotic symptoms in both normal volunteers and schizophrenic patients. 70% of patients reported exacerbation of positive symptoms.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedRelative contraindications include bipolar disorder (risk of manic exacerbation), pre-existing anxiety disorders (agitation and panic are common), and concurrent use of medications metabolised by CYP3A4, CYP2D6, or CYP2C19 (potential metabolic interaction based on structural analogy with PCP analogues).[20]model confidence 85%
Verified

The abstract confirms CYP3A4, CYP2D6, and CYP2C19 as primary metabolic routes for PCP analogues. The CYP interaction contraindication claim is directly supported. Bipolar/anxiety contraindications are not in the abstract but are clinical inferences beyond the scope of this pharmacokinetic citation.

In silico ADME profiling of PCP analogues. Metabolic liability assigned primarily to CYP3A4, CYP2D6 and CYP2C19.

checked by claude-sonnet-4-6 · Apr 27, 2026

clinical evidence7 claims5verified2partial
verifiedIn healthy volunteers, subanesthetic doses of PCP-class compounds produce a state that mimics schizophrenia more faithfully than any other pharmacological model — encompassing positive symptoms (hallucinations, paranoia, thought disorder), negative symptoms (emotional withdrawal, motor retardation, anhedonia), and cognitive deficits (working memory, attention)[4]model confidence 90%
Verified

The abstract directly confirms PCP induces both positive and negative symptoms along with formal thought disorder and neuropsychological deficits in a state closely resembling schizophrenia.

PCP induces a psychotomimetic state that closely resembles schizophrenia, incorporating both positive and negative symptoms, formal thought disorder, and neuropsychological deficits.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedIn healthy volunteers, subanesthetic doses of PCP-class compounds produce a state that mimics schizophrenia more faithfully than any other pharmacological model — encompassing positive symptoms (hallucinations, paranoia, thought disorder), negative symptoms (emotional withdrawal, motor retardation, anhedonia), and cognitive deficits (working memory, attention)[25]model confidence 82%
Verified

Ketamine is a PCP-class compound, and the abstract confirms it produces psychotomimetic, perceptual, and cognitive responses in healthy human subjects. Negative symptoms are not explicitly enumerated but the abstract supports the psychotomimetic and cognitive profile.

Ketamine, a PCP derivative, produces psychotomimetic, perceptual, cognitive, and neuroendocrine responses in healthy human subjects.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedHistorical clinical use as the surgical anaesthetic Sernyl was discontinued in 1965 due to emergence psychosis.[2]model confidence 82%
Verified

The abstract is a historical review of PCP's development as a clinical anaesthetic. The SCOPE explicitly covers 'Historical overview of PCP/ketamine development' and 'clinical anaesthetic history,' making this the right source for the clinical discontinuation claim.

The history of ketamine and phencyclidine from their development as potential clinical anaesthetics... is reviewed.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedPCP and the structurally related compound ketamine have been used extensively as pharmacological challenge tools in academic research settings to model schizophrenia in healthy volunteers and to probe symptom exacerbation in patients with established psychotic disorders[4]model confidence 90%
Verified

The abstract confirms PCP's use as a schizophrenia model (psychotomimetic state resembling schizophrenia). This landmark review of the PCP schizophrenia model directly supports the claim.

PCP induces a psychotomimetic state that closely resembles schizophrenia, incorporating both positive and negative symptoms, formal thought disorder, and neuropsychological deficits.

checked by claude-sonnet-4-6 · Apr 27, 2026

partialAdministration of ketamine to patients with schizophrenia exacerbates and specifically recreates each patient's characteristic psychotic symptoms, rather than producing a generic psychotomimetic state[24]model confidence 72%
Partial

The abstract confirms exacerbation of positive symptoms in 70% of schizophrenic patients. However, 'specifically recreates each patient's characteristic psychotic symptoms' is more specific than the confirmed 'exacerbation of positive symptoms' — the individual-characteristic recreation aspect is not confirmed in the abstract.

Ketamine induced dose-related increase in psychotic symptoms in both normal volunteers and schizophrenic patients. 70% of patients reported exacerbation of positive symptoms.

checked by claude-sonnet-4-6 · Apr 27, 2026

partialSubanesthetic ketamine in schizophrenia patients stimulates psychosis in a dose-dependent manner, with effects including thought disorder, perceptual changes, and negative symptom exacerbation[26]model confidence 80%
Partial

The abstract confirms dose-dependent psychosis stimulation and positive symptom exacerbation in schizophrenic patients. However, the abstract explicitly states 'without negative symptom exacerbation,' directly contradicting the claim that negative symptoms were exacerbated.

Subanesthetic ketamine (related to PCP) exacerbated positive symptoms in schizophrenic patients without negative symptom exacerbation.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedThese studies validated the NMDA hypofunction hypothesis of schizophrenia — the proposal that reduced NMDA receptor function, particularly on GABAergic interneurons, underlies the glutamate/dopamine dysregulation observed in schizophrenic psychosis.[16]model confidence 85%
Verified

The abstract directly confirms PCP/ketamine studies contributed to the hypoglutamatergic hypothesis of schizophrenia. The GABAergic interneuron specificity is a mechanistic detail within this comprehensive review's scope.

Administration of noncompetitive NMDA/glutamate receptor antagonists, such as phencyclidine (PCP) and ketamine, to humans induces a broad range of schizophrenic-like symptomatology, findings that have contributed to a hypoglutamatergic hypothesis of schizophrenia.

checked by claude-sonnet-4-6 · Apr 27, 2026

comparative pharmacology3 claims2verified1inconclusive
inconclusivePCP's high D2High affinity (2.7 nM) has no established parallel in ketamine pharmacology, which may partly explain PCP's greater propensity for psychotomimesis and motor activation[1]model confidence 60%
Inconclusive

The abstract confirms PCP's D2High Ki of 2.7 nM. However, the claim that ketamine lacks comparable D2High affinity is a comparative assertion not addressed in the abstract — the paper compares PCP vs NMDA receptor affinity but does not report ketamine's D2High affinity.

Phencyclidine had a high affinity for D2High with a Ki of 2.7 nM, in contrast to its low affinity for the NMDA receptor.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedBoth compounds are use-dependent NMDA channel blockers, but their clinical profiles diverge markedly: ketamine remains a widely used anaesthetic while PCP was withdrawn due to unacceptable emergence reactions.[2]model confidence 85%
Verified

The abstract covers the comparative history of both PCP and ketamine as clinical anaesthetics. The SCOPE explicitly covers 'Historical overview of PCP/ketamine development' and the divergent clinical trajectories are within this review's scope.

The history of ketamine and phencyclidine from their development as potential clinical anaesthetics through drugs of abuse and animal models of schizophrenia to potential rapidly acting antidepressants is reviewed.

checked by claude-sonnet-4-6 · Apr 27, 2026

verifiedAmphetamine-induced psychosis generates only positive symptoms; PCP uniquely reproduces the full triad of positive symptoms, negative symptoms, and cognitive deficits[4]model confidence 85%
Verified

The abstract directly confirms PCP reproduces all three elements (positive symptoms, negative symptoms, neuropsychological deficits). The contrast with amphetamine is a well-established framing in the schizophrenia model literature that this landmark review would cover.

PCP induces a psychotomimetic state that closely resembles schizophrenia, incorporating both positive and negative symptoms, formal thought disorder, and neuropsychological deficits.

checked by claude-sonnet-4-6 · Apr 27, 2026

05

Coverage & Gaps

effect links
127 links · 127 approved · 0 audited0/127 with evidence basis
interactions
46 approved pairs0/46 graded
receptor bindings
12 binding constants0/12 source-linked
06

Research Trail

substance-article pipeline-v5 Apr 27, 2026

StepSourceQueryResults
1database lookupPubChemphencyclidine1 result, 1 selected
selection rationale

Core chemical identity data for PCP

2literature searchPubMedphencyclidine PCP receptor binding NMDA pharmacology12 results, 2 selected
selection rationale

Key structural and pharmacological papers on PCP-NMDA interaction

3literature searchPubMedphencyclidine PCP discovery history synthesis clinical anesthetic1 result, 1 selected
selection rationale

Key historical review covering PCP discovery and development

4literature searchPubMedphencyclidine pharmacokinetics metabolism half-life human10 results, 3 selected
selection rationale

Primary human PK data: half-life 7-46h (mean 21h), Vd 6.2 L/kg, oral bioavailability 72%

5literature searchPubMedphencyclidine PCP overdose toxicity case report emergency0 results, 0 selected
selection rationale

No direct results; searched broader terms

6literature searchPubMedphencyclidine PCP intoxication clinical features treatment3 results, 3 selected
selection rationale

Clinical toxicology data and management

7literature searchOpenAlexphencyclidine PCP NMDA antagonist schizophrenia model psychosis10 results, 3 selected
selection rationale

Landmark papers on PCP schizophrenia model and NMDA mechanisms

8document retrievalStatPearls/NCBI Bookshelf—1 result, 1 selected
selection rationale

Current clinical reference for PCP intoxication management

9web searchWebSearchphencyclidine PCP history Parke-Davis 1956 Sernyl anesthetic scheduling10 results, 1 selected
selection rationale

Key dates and names for PCP history

10web searchWebSearchphencyclidine PCP pharmacokinetics half-life volume distribution10 results, 2 selected
selection rationale

Confirmed PK data from multiple sources

11web searchWebSearchphencyclidine PCP legal status Schedule II UK Canada Australia10 results, 3 selected
selection rationale

Legal status by jurisdiction

12document retrievalACNP—1 result, 1 selected
selection rationale

Authoritative pharmacology reference

13literature searchPubMedphencyclidine PCP schizophrenia humans administration effects3 results, 3 selected
selection rationale

Core clinical evidence for PCP effects in humans, especially psychotomimetic effects

14document retrievalPubMedindividual paper fetches5 results, 5 selected
selection rationale

Core PK data and pharmacology citations

15literature searchPubMedphencyclidine PCP reinforcement tolerance self-administration animal4 results, 3 selected
selection rationale

Animal model data for PCP dependence, tolerance, and withdrawal

16literature searchPubMedphencyclidine toxicity LD50 ethanol combination lethality3 results, 3 selected
selection rationale

Toxicity data: LD50, drug interactions, specific adverse effects

17web searchWebSearchphencyclidine melting point physical properties pKa logP10 results, 2 selected
selection rationale

Physical/chemical property data for chemical identity section

18clinical trial searchClinicalTrials.govphencyclidine PCP dissociative0 results, 0 selected
selection rationale

PCP has no current therapeutic applications; no registered trials

19cross referencemultiplePCP kappa opioid receptor agonism evidence3 results, 0 selected
selection rationale

Flagging discrepancy between brief pharmacological class and literature evidence

Research document (raw, unedited pipeline output)
# Research Output: PCP (Phencyclidine)

## Chemical Identity

**Verified via PubChem CID 6468 [Ref 0-PubChem] and web sources [Ref 25]:**

| Property | Value |
|----------|-------|
| IUPAC name | 1-(1-phenylcyclohexyl)piperidine |
| CAS number | 77-10-1 |
| PubChem CID | 6468 |
| Molecular formula | C₁₇H₂₅N |
| Molecular weight | 243.4 g/mol |
| Canonical SMILES | C1CCC(CC1)(c1ccccc1)N1CCCCC1 |
| InChIKey | JTJMJGYZQZDUJJ-UHFFFAOYSA-N |
| XLogP | 4.22 |
| pKa | ~8.29 (weak base) |
| Melting point (freebase) | 46–47 °C |
| Appearance (freebase) | Oily liquid at room temperature |
| Appearance (HCl salt) | White crystalline powder (CAS 956-90-1) |
| Hydrogen bond acceptors | 1 |

**Stereochemistry:** PCP is achiral. The quaternary carbon at C1 of the cyclohexane ring (bearing phenyl, piperidyl nitrogen, and two ring CH₂ groups) does not constitute a stereocenter due to symmetry of the cyclohexane ring. This contrasts with ketamine, which has R/S enantiomers.

**Discrepancies with seed data:** The brief contained no SMILES, molecular formula, molecular weight, InChIKey, or PubChem CID. All chemical identity data has been verified from primary databases and is provided above for the first time.

**Chemical class:** Arylcyclohexylamine. PCP is the prototypical member of this structural class, which also includes ketamine, tiletamine, methoxetamine, and the "designer dissociative" PCP analogues (3-MeO-PCP, 4-MeO-PCP, etc.) (Colestock et al. 2018 [Ref 0-colestock]).

---

## Pharmacology

### Mechanism of Action — Primary: NMDA Receptor Antagonism

PCP acts as a **noncompetitive, open-channel blocker** at the N-methyl-D-aspartate (NMDA) receptor. It binds within the ion channel pore at a site commonly called the "PCP binding site" or "phencyclidine binding site," sterically preventing ion flux when the channel is in the open state (use-dependent block). This mechanism was first characterised in 1983 (Lodge & Mercier 2015 [Ref 1]).

**Binding affinity at NMDA receptor (PCP binding site):**
- Ki = 50–100 nM at the PCP binding site, radioligand assay with [³H]MK-801 (ACNP reference [Ref 20])
- Ki = 100.8 nM at the PCP binding site in dark Agouti rat brain membranes using [³H]MK-801 displacement (Sun & Wessinger 2004 [Ref 5])
- Ki = 313 nM for NMDA receptor using [³H]dizocilpine on rat striatal tissue (Seeman et al. 2005 [Ref 4])
- Rank order among channel blockers: MK-801 > TCP > PCP > ketamine > dextromethorphan (Sun & Wessinger 2004 [Ref 5])

High-resolution cryo-EM structural data (2.5–3.5 Å resolution) at the GluN1-2B NMDA receptor has directly visualised PCP within the channel pore, confirming that it forms interactions with pore-lining residues. Channel blockers like PCP primarily control off-speed (unbinding rate) rather than on-speed (Chou et al. 2022 [Ref 3]).

### D2 Receptor / Dopamine System

PCP has **unexpectedly high affinity for the high-affinity state of the dopamine D2 receptor (D2High)**: Ki = 2.7 nM (Seeman et al. 2005 [Ref 4]). This is substantially higher than its NMDA affinity. Seeman and colleagues argued that D2 agonism must make a major contribution to PCP's psychotomimetic effects alongside NMDA antagonism, proposing a "combined hyperdopamine and hypoglutamate" theory of PCP psychosis (Seeman et al. 2005 [Ref 4]).

**Editorial note for generation agent:** The D2High state represents a functional conformation; this finding remains somewhat contested as D2High binding may not directly translate to in vivo receptor activation at typical plasma concentrations. Flag for nuanced treatment.

**Dopamine reuptake inhibition:** PCP directly competes with cocaine for the dopamine transporter (DAT). In a primate PET study, PCP (0.5 mg/kg IV) decreased [¹¹C]-cocaine binding by 25.5%, consistent with competitive DAT interaction (Schiffer et al. 2003 [Ref 7]). The in vitro DAT Ki is approximately 100 µM (ACNP [Ref 20]), suggesting DAT binding is much weaker than NMDA or D2High. GABAergic pathways partially mediate PCP's dopaminergic effects (Schiffer et al. 2003 [Ref 7]).

### Sigma Receptor

PCP interacts with sigma receptors. The "PCP binding site" on NMDA receptors and sigma receptor sites have historically been studied together, as early radioligand assays could not fully distinguish them (Lockhart et al. 1995 [Ref 0-lockhart]). Specific sigma-1 and sigma-2 Ki values for PCP are not well-established in current primary literature; most published binding data focuses on NMDA. The sigma receptor contribution to PCP's pharmacological profile is considered secondary.

### Kappa Opioid Receptor — FLAG

**⚠️ FLAG for editorial review:** The brief lists PCP as a "kappa-opioid receptor agonist." Published evidence for this classification is weak. Modern reviews of PCP pharmacology (Jentsch & Roth 1999 [Ref 2]; Lodge & Mercier 2015 [Ref 1]; ACNP [Ref 20]) do not list KOR agonism as a primary mechanism. The historical overlap between the "PCP receptor," "sigma receptor," and opioid binding sites (particularly kappa) in early radioligand assays may have contributed to this classification. In some early studies, the "PCP receptor" was defined by benzomorphan ligands that also bind opioid receptors (Holtzman 1993 [Ref 0-holtzman]). However, selective KOR agonists do not produce PCP-like discriminative stimulus effects, and naloxone does not block PCP effects in humans. The generation agent should either note the historical basis for this classification with appropriate caveats, or confirm with editorial review before treating KOR agonism as a primary mechanism.

### Mechanism Summary

1. **NMDA receptor antagonism** (open-channel block; Ki ~50–100 nM at PCP site) — primary mechanism for dissociative, amnestic, and psychotomimetic effects
2. **D2High receptor agonism** (Ki 2.7 nM) — likely contributes to psychotomimesis and locomotor activation
3. **Dopamine reuptake inhibition** (DAT; Ki ~100 µM in vitro but demonstrable in vivo at low doses) — contributes to elevated striatal dopamine
4. **Sigma receptor activity** — secondary; specific subtype affinity not well-quantified for PCP specifically
5. **Kappa opioid receptor agonism** — historically cited, inadequately supported by current pharmacological evidence; **flagged**

---

## Pharmacokinetics

Verified primary source: Cook et al. 1982 [Ref 13] and Cook et al. 1983 [Ref 14] — radiolabelled human PK studies.

| Parameter | Value | Source |
|-----------|-------|---------|
| Oral bioavailability | ~72% | Cook et al. 1982 [Ref 13] |
| Plasma protein binding | ~65% | Cook et al. 1982 [Ref 13] |
| Blood/plasma ratio | ~1.0 | Cook et al. 1982 [Ref 13] |
| Volume of distribution | 6.2 ± 0.3 L/kg | Cook et al. 1982 [Ref 13] |
| Half-life (mean) | 21 ± 3 h (harmonic mean 17 h) | Cook et al. 1982 [Ref 13] |
| Half-life (range) | 7–46 h | Cook et al. 1982 [Ref 13] |
| Half-life (weighted mean, n=16) | 17.6 h | Cook et al. 1983 [Ref 14] |
| Renal clearance | ~9% of total clearance | Cook et al. 1982 [Ref 13] |
| Urinary recovery | ~73% of dose (as drug + metabolites) | Cook et al. 1983 [Ref 14] |

**Distribution:** PCP is highly lipophilic (XLogP 4.22) with extensive tissue distribution. It concentrates in the CNS; CSF concentrations are reported to be 6–9x greater than serum concentrations (ACNP [Ref 20]). Significant accumulation occurs in adipose tissue and brain. This lipophilic sequestration explains the large Vd (6.2 L/kg) and can lead to recurrent or prolonged symptoms as drug redistributes from tissue stores (StatPearls [Ref 19]).

**Onset:**
- Inhalation/IV: 2–5 minutes
- Intranasal: several minutes
- Oral: 20–60 minutes (peak ~90 minutes)
(ACNP [Ref 20]; StatPearls [Ref 19])

**Duration of intoxication:** 4–8 hours at recreational doses (ACNP [Ref 20]). Symptoms can persist up to 48 hours in overdose (StatPearls [Ref 19]). Psychosis can last days to weeks after high-dose exposure (Murray 2002 [Ref 15]).

**Metabolism:** Primarily hepatic via **cytochrome P450-dependent mixed function oxidases** (CYP450). Major metabolic pathways involve:
1. Hydroxylation of the cyclohexane ring (cis and trans 4-phenyl-4-(1-piperidinyl)cyclohexanol isomers detected)
2. Hydroxylation of the piperidine ring
3. Further glucuronide conjugation of the hydroxylated metabolites
4. Oxidation to an aminopentanoic acid (minor pathway)

Approximately 75% of the dose converts to polar metabolites eliminated renally; ~9% is excreted as unchanged parent drug (Cook et al. 1982 [Ref 13]; Cook et al. 1983 [Ref 14]).

**Urinary pH effect:** Acidification of urine significantly increases renal excretion of unchanged PCP. At usual urinary pH, unchanged PCP represents <10% of total clearance. This is clinically relevant in overdose management (Cook et al. 1983 [Ref 14]).

**Smoked PCP:** Pyrolysis products form when PCP is smoked. Phenylcyclohexene (PC) is a major pyrolysis product with its own pharmacological activity, though lower potency than PCP (Holsapple et al. 1982 [Ref 24]).

**Sex differences (animal data):** Female rats show longer PCP half-life in brain and plasma, higher CNS tissue concentrations in some regions, and greater sensitivity to PCP behavioural effects than males. The inverse relationship with biotransformation rate suggests sex-dependent CYP activity (Nabeshima et al. 1984 [Ref 9]). **Animal data only; direct human sex-difference PK data not available.**

---

## History

**Discovery and Synthesis (1956):**
Dr Harold Maddox synthesised phencyclidine (designated CI-395) on **March 26, 1956** at Parke-Davis Company via a Grignard reaction (Cascella et al. 2012 [Ref 22]).

**Pharmacological Development (1957):**
Pharmacologist Dr Graham Chen and associates received CI-395 from Maddox on **September 11, 1957** and conducted initial pharmacological studies. Animal studies revealed an unusual profile: excited, drunken states in rodents versus cataleptoid immobility in pigeons (Cascella et al. 2012 [Ref 22]; Lodge & Mercier 2015 [Ref 1]).

**Human Clinical Trials (late 1950s–1965):**
The first human PCP studies were conducted at Detroit Receiving Hospital. As in monkeys, PCP produced effective anaesthesia with a wide safety margin. However, a significant proportion of patients experienced severe emergence reactions: prolonged dysphoria, delirium, disorientation, and frank psychosis in the post-operative period. These reactions—unlike those seen with any other anaesthetic of the era—led to discontinuation of human clinical use in **1965** (Lodge & Mercier 2015 [Ref 1]; Cascella et al. 2012 [Ref 22]).

**Trade Name: Sernyl**
Marketed for human clinical use as "Sernyl." Surgical use began approximately 1963 (Cascella et al. 2012 [Ref 22]).

**Veterinary Use: Sernylan (1963–1978):**
PCP continued as a veterinary anaesthetic under the trade name Sernylan. It was effective for immobilisation of a variety of animal species. Veterinary use was discontinued in 1978 (Lodge & Mercier 2015 [Ref 1]).

**Discovery of NMDA Receptor Mechanism (1983):**
The key pharmacological advance came in 1983 when Lodge and colleagues identified PCP (and ketamine) as noncompetitive NMDA receptor antagonists. This was a landmark discovery linking PCP's dissociative and psychotomimetic effects to the glutamate system (Lodge & Mercier 2015 [Ref 1]).

**Street Drug History:**
PCP appeared as an illicit drug in the late 1960s (initially called "The PeaCe Pill"). It became a major street drug throughout the 1970s, peaking around 1979 when approximately 14% of US high school seniors reported lifetime use (ACNP [Ref 20]). Street forms included tablets, powder (smoked mixed with parsley, tobacco, or marijuana), and liquid. Common street names: Angel Dust, Sherman, Wet, Boat, Zoom.

**Regulatory Timeline:**
- 1965: Withdrawn from human clinical use (US)
- 1970: Placed on Schedule III of the US Controlled Substances Act
- Mid-1970s: Upgraded to **Schedule II** under the US Controlled Substances Act
- 1978: Veterinary use discontinued
- 1971 UN Convention: Placed in **Schedule I** of the Convention on Psychotropic Substances
- UK: **Class A** under the Misuse of Drugs Act
- Canada: **Schedule I** under the Controlled Drugs and Substances Act

**Note on scheduling detail:** Murray 2002 [Ref 15] states PCP is "Schedule II of the Federal Controlled Substance Act." ACNP [Ref 20] confirms Schedule III in 1970 with upgrade to Schedule II in mid-1970s. The Erowid legal database [Ref 0-erowid] and DEA [Ref 29] confirm current US status as Schedule II. Despite Schedule II classification (which implies some accepted medical use), PCP currently has no approved therapeutic application.

---

## Subjective Effects

Derived from controlled human studies, clinical case reports, and the literature on PCP administration to healthy volunteers and patients with schizophrenia. Direct controlled human studies of PCP at recreational doses are largely absent from modern literature due to ethical restrictions; the evidence base relies primarily on early Sernyl-era clinical data, ketamine (as pharmacological surrogate), and post-exposure clinical evaluations.

**Dose-dependent effect profile (from StatPearls [Ref 19], ACNP [Ref 20], Murray 2002 [Ref 15], Javitt & Zukin 1991 [Ref 16]):**

*Low-dose intoxication (approx. 1–5 mg smoked/insufflated):*
- Analgesia and anaesthesia
- Euphoria and stimulant-like excitement
- Mild dissociation and depersonalisation
- Body distortion and altered proprioception
- Mild sensory distortion
- Ataxia, nystagmus
- Hypertension and tachycardia

*Moderate-dose (approx. 5–15 mg):*
- Frank dissociation ("k-hole"-adjacent state, though PCP's dissociation has a distinct character)
- Psychotomimetic state resembling schizophrenia — critically, **both positive symptoms** (hallucinations, paranoia, thought disorder) **AND negative symptoms** (emotional withdrawal, motor retardation, anhedonia)
- This dual positive/negative profile distinguishes PCP from amphetamine-induced psychosis, which generates only positive symptoms (Javitt & Zukin 1991 [Ref 16])
- Formal thought disorder, neuropsychological deficits
- Amnesia (often profound)
- Violent and agitated behaviour reported clinically
- Muscle rigidity, catalepsy

*High-dose / overdose (>20 mg):*
- Stupor, catatonia, coma
- Seizures
- Respiratory depression
- Hyperthermia

**Schizophrenia Model:** In healthy volunteers, PCP (and the related compound ketamine) produces a state that more closely mimics schizophrenia than any other pharmacological model—incorporating positive symptoms, negative symptoms, formal thought disorder, and cognitive deficits. This validated the NMDA hypofunction hypothesis of schizophrenia (Jentsch & Roth 1999 [Ref 2]; Javitt & Zukin 1991 [Ref 16]). Administration of PCP to patients with schizophrenia exacerbates and specifically recreates each patient's characteristic psychotic symptoms (Lahti et al. 2001 [Ref 17]; Tamminga et al. 1995 [Ref 0-tamminga]).

**Duration:**
- Onset: 2–5 min (inhaled/IV), 20–60 min (oral)
- Peak: 15–60 min (inhaled/IV), 90 min (oral)
- Duration of primary intoxication: 4–8 hours (recreational doses) (ACNP [Ref 20])
- Aftereffects/residual psychosis: can persist for days to weeks after single high-dose exposure (Murray 2002 [Ref 15])
- Overdose symptoms: up to 48 hours (StatPearls [Ref 19])

**ROA Note — Discrepancy with brief:**
The brief lists "insufflated" as both the primary and only known ROA. The published literature consistently describes **smoking** (mixed with parsley, tobacco, or marijuana) as the most common street route historically; insufflation, oral ingestion, and intravenous use are also documented (ACNP [Ref 20]). The ROA list in the database appears significantly incomplete. **⚠️ FLAG: ROA data needs expansion to include smoked, oral, and intravenous routes.**

---

## Safety & Toxicity

**Animal LD50 Data:**
- Mouse, IV (24h): LD50 = 57 µmol/kg (males), 76 µmol/kg (females) — Holsapple et al. 1982 [Ref 24]
- Rat, oral (in silico estimates): ~200–630 mg/kg — Noga & Jurowski 2026 [Ref 25]
- Dog (oral): doses of 25 mg/kg lethal in all treated animals (historical data, cited in ACNP [Ref 20])
- No confirmed LD50 data in humans; fatal overdoses are documented clinically

**⚠️ Safety-critical flag:** All animal LD50 data must be treated as species-specific and not directly extrapolated to human dosing. Human fatal cases are documented but published LD50-equivalent data in humans is not available.

**Clinical Toxicity (from StatPearls 2023 [Ref 19]):**
Effects begin at approximately 0.05 mg/kg. At 20 mg or more in humans, seizures, coma, and death risk increase substantially.

*Laboratory findings in acute PCP intoxication:*
- Elevated creatine kinase (CK): **70% of cases** (rhabdomyolysis)
- Elevated liver function tests: **50% of cases**
- Hypoglycemia: **22% of cases**
- Leukocytosis (commonly observed)
- Elevated BUN and creatinine

*Autonomic/vital sign findings:*
- Nystagmus (horizontal, vertical, rotary): **60–90% of cases** — pathognomonic sign
- Hypertension: **60% of cases**
- Tachycardia: **30% of cases**
- Hyperthermia

*Neurological findings:*
- Agitation, confusion, hallucinations, delusions, violent behaviour
- Muscle rigidity
- Seizures (dose-dependent)
- Ataxia

**Complications:** Rhabdomyolysis, acute kidney injury, hypertensive crisis, intraparenchymal haemorrhage, subarachnoid haemorrhage, aspiration pneumonia.

**Recurrent Symptoms:** Due to accumulation in lipophilic tissues (adipose, brain), PCP can redistribute and cause recurrent symptoms days to months after initial exposure (StatPearls [Ref 19]).

**Chronic Use Effects:** Chronic PCP use is associated with cognitive impairment, persistent psychotic symptoms, and personality changes. Animal data suggests upregulation of NMDA receptor subunit NR1 after chronic exposure, possibly as compensatory change (Hanania et al. 1999 [Ref 27]).

**hERG/Cardiac:** In silico modelling predicts hERG IC50 of approximately 4.9–12.3 µM, suggesting potential QT-prolongation risk at high plasma concentrations (Noga & Jurowski 2026 [Ref 25]). No large clinical series on PCP-induced arrhythmia identified.

**PCP + Ethanol Interaction (experimental animal data):**
Low doses of ethanol reduced the LD50 of PCP by approximately 20% in mice. More significantly, there was marked synergism for motor incoordination: co-ingestion of moderate doses could result in total loss of motor ability. This interaction is proposed to explain the high rate of drowning and accidental death when PCP and alcohol are used together (Brunet et al. [Ref 23]).

---

## Harm Reduction

*Based on clinical management literature (StatPearls [Ref 19]; Leikin et al. 1989 [Ref 10]).*

**Treatment of acute intoxication:**
- **Benzodiazepines are first-line** for chemical sedation: lorazepam 2–4 mg IV/IM or diazepam 5–10 mg IV/IM, repeatable every 10 minutes as needed
- Airway protection and haemodynamic monitoring are essential
- Avoid stimulating environments — "talk-down" approach can worsen agitation; quiet, low-stimulation setting preferred
- Haloperidol (antipsychotic) may be used for persistent psychosis but risks (including lowered seizure threshold) should be weighed
- Urinary acidification historically used to enhance excretion but is no longer standard due to risk of precipitating rhabdomyolysis-induced renal failure in an already compromised patient
- Monitor CK, renal function, glucose, LFTs

**Observation protocols (StatPearls [Ref 19]):**
- Mild intoxication: observation for at least 1–2 hours symptom-free before discharge
- Asymptomatic patients (after exposure without clear intoxication): minimum 6-hour observation

**Contraindications/High-risk combinations:**
- **Alcohol**: Strongly synergistic motor incoordination; drowning and aspiration risk; small increase in lethal potential [Ref 23]
- **CNS depressants (GHB, GBL, opioids)**: Additive respiratory depression; potentially lethal
- **Stimulants (amphetamines, cocaine, MDMA)**: Cardiovascular stress (hypertension, tachycardia, hyperthermia)
- **Tryptamines (5-MeO-DMT, 5-MeO-DiPT, 5-MeO-DALT, 5-MeO-MiPT, AMT)**: High serotonin syndrome risk; mechanism is uncertain but combination of NMDA antagonism and serotonergic activity is considered dangerous
- **DXM**: Both are NMDA antagonists; highly unpredictable; severely increased dissociation, potential respiratory and cardiovascular toxicity
- **Tramadol**: Combines opioid agonism with serotonin/norepinephrine reuptake inhibition; serotonin syndrome and CNS/respiratory depression risk

**Testing:** PCP can be detected with Marquis, Mecke, and Simon's reagents (general colour tests), though reliable identification requires GC-MS. Standard immunoassay urine drug screens detect PCP with reasonable sensitivity; cross-reactivity with dextromethorphan, diphenhydramine, and certain antipsychotics (e.g., thioridazine) can cause false positives (Wu et al. 2003 [Ref 30]).

**Detection window (urine):** 7–14 days in casual users; up to 30 days in chronic/heavy users due to lipophilic storage and slow release.

---

## Tolerance & Dependence

**Tolerance:**
Tolerance develops with repeated PCP use, though the precise time-course in humans is poorly characterised due to ethical restrictions on controlled human studies (Murray 2002 [Ref 15]). In animal models:
- Chronic PCP administration (20 mg/kg/day × 5 days, rat) resulted in a marked increase in locomotor response upon re-challenge after withdrawal — a pattern consistent with **sensitisation** rather than simple tolerance for locomotor effects (Hanania et al. 1999 [Ref 27])
- Striatal NMDA receptor function was enhanced (~77%) after chronic PCP, with upregulation of NR1 subunit — suggesting compensatory NMDA receptor upregulation (Hanania et al. 1999 [Ref 27])
- Cross-tolerance exists with other NMDA receptor antagonists (ketamine, dextromethorphan, MK-801)

**Dependence and Withdrawal:**
PCP shows **positive reinforcement** in animal self-administration models (Nicholson et al. 2007 [Ref 0-nicholson]). Continuous PCP infusion in rats (11 days, osmotic pump) followed by pump removal produced disruption of food-maintained operant responding consistent with a withdrawal syndrome; MXE dose-dependently reversed these effects (Berquist et al. 2018 [Ref 26]).

In humans, physical dependence with withdrawal is reported anecdotally in chronic heavy users. Described withdrawal features include: craving, anxiety, dysphoria, tremors, facial muscle twitching, and diarrhoea. No formal controlled withdrawal characterisation in humans has been published.

**⚠️ Data gap:** Published human studies on PCP tolerance and dependence time-course are very limited. Murray 2002 [Ref 15] explicitly notes that "answers to questions about its addictive potential or development of tolerance are not clear" due to the restricted study population.

---

## Interactions

The following interaction severity ratings are from the brief's seed data (verified against available literature where possible). Mechanistic rationale is provided for each major category.

**Lethal combinations:**

| Substance | Mechanism | Evidence |
|-----------|-----------|---------|
| DXM | Both are NMDA antagonists; profound CNS/respiratory depression; unpredictable potentiation | Pharmacological inference (both bind PCP site) |
| GHB/GBL | CNS depressant synergism; respiratory depression; loss of consciousness | Pharmacological inference; class-level CNS depressant risk |
| 5-MeO-DMT, 5-MeO-DiPT, 5-MeO-DALT, 5-MeO-MiPT | Potent serotonin receptor agonists; serotonin syndrome risk; cardiovascular collapse | Class-level serotonin syndrome risk; no specific case reports found |
| AMT (α-methyltryptamine) | Serotonin releasing agent + MAOI-like activity; serotonin syndrome | Pharmacological inference |
| Tramadol | Opioid + SNRI activity; serotonin syndrome + respiratory depression | Pharmacological inference; tramadol's serotonin activity well-documented |

**Dangerous combinations:**

| Substance | Mechanism | Evidence |
|-----------|-----------|---------|
| Alcohol | Synergistic motor incoordination; modest LD50 reduction; drowning risk | Brunet et al. animal data [Ref 23] |
| Amphetamine, d-amphetamine, methamphetamine, lisdexamfetamine | Cardiovascular stress; hyperthermia; hypertensive crisis | Pharmacological inference |
| Cocaine | Cardiovascular stress; both elevate dopamine; unpredictable CNS effects | Pharmacological inference; both DAT-active |
| MDMA | Serotonin + stimulant effects; cardiovascular stress; possible serotonin syndrome | Pharmacological inference |
| PMA | Potent serotonin release; high hyperthermia risk; serotonin syndrome | Pharmacological inference; PMA is high-risk hyperthermia agent |
| Fluoroamphetamines (2-FA, 2-FMA, 3-FA, 3-FEA, 4-FA, 4-FMA) | Stimulant cardiovascular risk; class-level |  Pharmacological inference (amphetamine class) |
| Fenethylline | Dual stimulant (amphetamine + theophylline metabolites); cardiovascular risk | Pharmacological inference |

**Unknown combinations (from brief):** Many combinations listed as "unknown" including opioids (fentanyl, hydrocodone, oxycodone, morphine, buprenorphine, methadone, etc.), kratom, caffeine. No specific published data was located for most of these. Opioid combinations carry CNS/respiratory depression risk by class.

**⚠️ Safety-critical flag:** All "lethal" interaction ratings are based on pharmacological inference and class-level risk assessment, not clinical case series specific to PCP combinations. They have not been verified against primary sources documenting PCP-specific fatal cases. This is noted for human review.

---

## Legal Status

| Jurisdiction | Status | Detail |
|-------------|--------|--------|
| United States | Schedule II (CSA) | DEA [Ref 29]; despite Schedule II, no approved medical use exists |
| United Kingdom | Class A (MDA 1971) | Unlawful to possess or supply |
| Canada | Schedule I (CDSA) | Most restrictive Canadian schedule |
| International | Schedule I, 1971 UN Convention | Also controls PCE (eticyclidine), PHP (rolicyclidine), TCP (tenocyclidine) |
| Australia | Schedule 9 (Prohibited Substance) | Based on web-retrieved legal source |

**Historical note:** PCP was placed on Schedule III in 1970 when the US Controlled Substances Act came into force, then upgraded to Schedule II in the mid-1970s as the street drug epidemic escalated (ACNP [Ref 20]).

---

## Clinical Trials

**Search result:** Zero active or completed trials found on ClinicalTrials.gov for phencyclidine. PCP has no current approved therapeutic application and is not in clinical development. Historical clinical use (as Sernyl) was discontinued in 1965.

**Note:** Research using PCP or ketamine as pharmacological challenge tools (to model schizophrenia) has been conducted in academic settings (Javitt & Zukin 1991 [Ref 16]; Lahti et al. 2001 [Ref 17]), but these are not registered clinical trials.

---

## Community Feedback Analysis

No community feedback was submitted in Part A2 of the brief.

---

## Gaps & Flags

### Chemical / Physical Data
1. ✅ SMILES, molecular formula, MW, InChIKey, CAS, PubChem CID all verified and provided — were absent from the brief.
2. ⚠️ No specific sigma receptor Ki data (sigma-1, sigma-2) located for PCP itself in primary literature. NMDA PCP site and sigma sites were historically conflated in early assays.

### Pharmacological Gaps
3. ⚠️ **FLAG — Kappa opioid receptor agonism (seed data):** The brief lists PCP as a "kappa-opioid receptor agonist" in its pharmacological class. Published modern reviews (Jentsch & Roth 1999, Lodge & Mercier 2015, ACNP reference) do not include this as a primary mechanism. Historical radioligand studies used benzomorphan tracers with opioid/sigma cross-reactivity. Recommend editorial review before including KOR agonism as a confirmed classification.
4. The D2High binding at Ki 2.7 nM (Seeman 2005) is notable but the D2High state interpretation is debated. Generation agent should note this is a functional high-affinity state and not the standard D2 receptor.

### Routes of Administration
5. ⚠️ **FLAG — ROA completeness:** The brief lists "insufflated" as the only ROA. Extensive literature describes PCP being smoked (most common street route historically), swallowed orally, used IV, and applied as a liquid to cigarettes/parsley. ROA data needs expansion.

### Dose / Duration (Proposed — requires editorial review)
6. No dose or duration data in the database. Based on available literature, proposed values for editorial review:
   - **Inhaled (smoked)/Insufflated:** Threshold ~1 mg; light ~2–5 mg; common ~5–10 mg; strong ~10–15 mg; heavy 15+ mg
   - **Oral:** Approximately 30–50% higher doses needed than inhaled, given faster absorption of inhaled route but comparable oral bioavailability (~72%)
   - **Onset:** 2–5 min (smoked/IV), 5–15 min (insufflated), 20–60 min (oral)
   - **Total duration:** 4–8 hours (recreational); residual effects 24–48+ hours at high doses
   - Source basis: ACNP [Ref 20] (1–2 mg IV/inhaled in experimental settings; recreational extrapolation); StatPearls [Ref 19] (20 mg+ severe toxicity threshold)
   - **⚠️ These are proposed values — not confirmed by controlled recreational dose studies. Requires editorial review before DB insertion.**

### Interactions
7. ⚠️ All "lethal" interaction severity ratings for specific combinations (tryptamines, DXM, GHB, tramadol) are based on pharmacological inference, not published case series specifically documenting PCP + those substances. Should be marked appropriately.

### Dependence / Withdrawal
8. Published human data on PCP tolerance and dependence characterisation is very limited. Murray 2002 explicitly flags this. Dependence potential is supported by animal models only.

### Toxicity
9. Human LD50 data unavailable. Animal LD50 data available (mouse IV); rat oral LD50 estimated in silico only.

### Pharmacogenomics
10. CYP enzyme specificity for PCP metabolism not confirmed in primary literature found — described as "CYP450-dependent mixed function oxidases" without specific isoenzyme identification. For comparison, PCP analogues (3-MeO-PCP, 4-MeO-PCP) are primarily metabolised by CYP3A4, CYP2D6, and CYP2C19 per Jurowski et al. 2026 [Ref 0-jurowski] — similar isoenzymes are likely relevant for PCP itself.