Understanding Phencyclidine Intoxication: Types, Symptoms, and Treatment
Emergency Medicine • Toxicology • Psychiatry
Understanding Phencyclidine (PCP) Intoxication: Types, Symptoms, and Treatment
A focused clinical guide for frontline clinicians on recognizing PCP intoxication, immediate management of agitation and medical complications, and appropriate follow‑up and referral.
Substances & epidemiology
PCP is a dissociative anesthetic; related agents include ketamine and designer dissociatives. Use is sporadic in many settings but can lead to severe presentations requiring emergency care.
Types of intoxication
- Acute dissociative intoxication — marked derealisation, hallucinations and analgesia.
- Agitated/violent intoxication — severe psychomotor agitation and combativeness.
- Medical complications — hyperthermia, rhabdomyolysis, seizures, aspiration and trauma from risky behaviour.
Key recognition features
- Behavioral: unpredictable agitation, combativeness, decreased responsiveness to pain.
- Neurological: prominent nystagmus (vertical/horizontal), ataxia, confusion, and possible seizures.
- Autonomic: hypertension, tachycardia, diaphoresis, hyperthermia.
- Clues: chemical bowls, powders, reports from bystanders; tox screens are often limited for PCP.
Immediate management
- Ensure safety: remove potential weapons, minimise staff exposure, and consider security if violent behavior threatens safety.
- Calm, low‑stimulus environment with verbal de‑escalation; avoid confrontation.
- Benzodiazepines first‑line for agitation (e.g., lorazepam 2–4 mg IV/IM, repeat to effect) — titrate carefully and monitor respiratory function.
- Consider antipsychotics (e.g., haloperidol) when severe psychosis or agitation persists despite benzodiazepines — monitor for QTc prolongation and seizures.
Treating medical complications
- Hyperthermia: rapid cooling measures, IV fluids, and treat underlying agitation; monitor CK for rhabdomyolysis.
- Rhabdomyolysis: measure CK and renal function, ensure adequate urine output, IV fluids and consider ICU for severe cases.
- Seizures: treat with benzodiazepines and manage airway/support; consider further anticonvulsant if recurrent.
- Aspiration: manage airway, give oxygen, consider chest imaging and antibiotics if infection suspected.
Disposition & observation
- Monitor for at least 6–24 hours depending on severity — longer if hyperthermia, rhabdomyolysis, seizures or ongoing agitation.
- Admit to ICU if unstable vitals, severe hyperthermia, renal impairment from rhabdomyolysis, or refractory agitation requiring parenteral sedation.
- Psychiatric assessment and safety planning prior to discharge for patients with persistent psychosis or suicidality.
Follow‑up & rehabilitation
- Arrange addiction services referral for recurrent users and community mental health for those with persistent psychiatric symptoms.
- Provide education on risks, harm reduction, and avoiding polysubstance use that increases medical risk (stimulants, alcohol).
- Consider occupational and social supports for those affected by injury or ongoing functional impairment.
Red flags — urgent escalation
- Severe hyperthermia (>39°C), seizures, uncontrolled agitation, suspected rhabdomyolysis with rising CK/renal impairment — urgent ICU care.
- Respiratory compromise or aspiration — secure airway and escalate to ED/ICU.
- Violence with risk of serious harm — ensure immediate safety measures and involve security/police as needed.
Case vignette
Patient: S., 24, brought in after being aggressive at a party following suspected PCP use. In ED S. had prominent vertical nystagmus, temp 39.2°C and CK 1800. Managed with repeated lorazepam, cooling and IV fluids; admitted for observation and CK monitoring. Referred to addiction outreach on discharge.
தமிழில் — சுருக்கம்
PCP போன்ற மருந்துகள் தீவிர பதட்டம், ஆபத்தான நடத்தைகள் மற்றும் உடல்நிலை பிரச்சினைகளை ஏற்படுத்தும். ஆரம்ப சிகிச்சை அமைதிப்படுத்தல், பென்சோடியாஸிபைன்கள் மற்றும் உடல்நிலை ஆதரவு; தீவிர அறிகுறிகள் இருந்தால் ICU தேவை.
Key takeaways
- PCP intoxication can be medically and behaviourally severe — prioritise staff and patient safety, control agitation with benzodiazepines, and treat complications like hyperthermia and rhabdomyolysis.
- Monitor patients for delayed complications and ensure psychiatric/addiction follow‑up where needed.