Spectrum of PCP/dissociative‑induced disorders

• Persistent psychosis or substance‑induced psychotic disorder following repeated exposure.
• Prolonged dissociative states and depersonalisation/derealisation beyond acute intoxication.
• Ketamine‑related urological disease (cystitis, lower urinary tract symptoms) with chronic use.
• Neurocognitive impairment after repeated or high‑dose exposure: memory, attention and executive function deficits.
• Mood and anxiety disorders precipitated or worsened by dissociative use.

Recognition & assessment

1. Detailed history: identify substance(s), frequency, dose, route, setting, onset and persistence of symptoms relative to last use.
2. Screen for psychosis: hallucinations, delusions, thought disorder and assess duration — differentiate acute intoxication from a persisting psychotic disorder.
3. Assess dissociative symptoms using structured questions (episodes of depersonalisation/derealisation, functional impact) and screen for PTSD or trauma history which may co‑occur.
4. Investigate urinary symptoms thoroughly in suspected chronic ketamine users — urgency, frequency, haematuria, dysuria and reduced bladder capacity; refer to urology where indicated.

Differential diagnosis

• Primary psychotic disorders (schizophrenia) — consider family history, premorbid functioning, and persistence after prolonged abstinence.
• Primary dissociative or trauma‑related conditions — evaluate for PTSD and dissociative identity disorder where history suggests.
• Neurological causes of cognitive impairment — consider neuroimaging and neuropsychological testing for atypical features or progressive course.

Investigations

• Toxicology where available to confirm recent exposure; basic labs to exclude metabolic causes (electrolytes, thyroid, B12) and infection.
• MRI brain if focal deficits, progressive cognitive decline or atypical features suggest structural pathology.
• Urinalysis, ultrasound and urodynamic studies for suspected ketamine cystitis; refer early to urology for severe symptoms.
• Neuropsychological testing for persistent cognitive complaints to guide rehabilitation planning.

Management principles

• Encourage and support abstinence from dissociatives; counsel on risks of persistent symptoms and provide harm‑reduction advice for those not ready to stop.
• Treat acute psychiatric symptoms: benzodiazepines for severe anxiety/agitation in the short term; antipsychotics for persistent psychosis under psychiatric supervision.
• Address comorbid mood and anxiety disorders with evidence‑based therapies (CBT, SSRIs) while monitoring for interactions with substance use.
• Coordinate multidisciplinary care — psychiatry, addiction services, neurology, urology (for ketamine cystitis), and rehabilitation services for cognitive deficits.

Specific management areas

Persistent psychosis

• Consider a trial of antipsychotic medication when psychotic symptoms persist beyond intoxication and cause impairment; use lowest effective dose and monitor side effects.
• Reassess diagnosis after a period of sustained abstinence — some cases resolve, while others may reveal a primary psychotic disorder.

Dissociative and depersonalisation states

• Psychological therapies (trauma‑focused CBT, grounding, mindfulness) are first‑line; pharmacological options have limited evidence.
• Provide safety planning for patients with high anxiety or self‑harm risk and consider specialist referral for complex dissociation.

Ketamine‑related uropathy

• Mainstay is abstinence and urological management — anticholinergic agents, bladder instillations, and in severe cases surgical interventions may be needed.
• Early referral to urology improves outcomes; manage comorbid infections and provide pain control and pelvic physiotherapy where appropriate.

Neurocognitive impairment

• Cognitive rehabilitation, occupational therapy and structured psychosocial interventions support recovery; consider neurology referral for persistent or progressive deficits.

When to refer

• Persistent psychosis, severe dissociation, ongoing suicidal ideation or functional decline — urgent psychiatric referral.
• Severe lower urinary tract symptoms suggestive of ketamine cystitis — urology referral without delay.
• Progressive cognitive impairment or focal neurological signs — neurology and neuropsychology referral.

Key takeaways

• Dissociative substances can cause long‑term psychiatric, cognitive and urological problems beyond acute intoxication.
• Early identification, sustained abstinence and multidisciplinary care (psychiatry, addiction services, urology, neurology) improve outcomes.
• Use presentations as opportunities to engage patients with tailored treatment plans and harm‑reduction strategies.