Psychosis & Schizophrenia

Overview – Psychosis & Schizophrenia

Psychosis & schizophrenia encompass a range of psychiatric disorders characterised by impaired reality testing, including hallucinations and delusions. These disturbances can severely impair functioning and often present in a variety of contexts including primary psychotic disorders, mood disorders, or medical conditions. Schizophrenia is a chronic and severe subtype, distinguished by persistent symptoms lasting over six months. Accurate diagnosis and early intervention are key to improving long-term outcomes.

Definition

• Psychosis: Cognitive or behavioural disturbance involving:
  • Inability to recognise or accurately interpret reality
  • Presence of delusions (false, fixed beliefs) or hallucinations (perceptual experiences without external stimuli)
• Delusions: Firmly held false beliefs, even when presented with clear evidence to the contrary
• Hallucinations: Sensory perceptions (e.g., hearing voices) without external stimuli, potentially affecting any sensory modality

Classification by Duration

• Brief Psychotic Disorder: <1 month duration
• Schizophreniform Disorder: 1–6 months
• Schizophrenia: >6 months

Differential Diagnosis

• Primary Psychotic Disorders: Schizophrenia, schizophreniform, brief psychotic disorder
• Mood Disorders with Psychotic Features: Major depression, bipolar disorder
• Personality Disorders: Schizotypal, schizoid, borderline, paranoid
• Organic/Medical Causes:
  • Brain tumour, stroke, head trauma
  • Dementia, delirium
  • Infections (e.g., encephalitis)

Acute Psychosis Management

1. Ensure safety (patient and staff)
2. Reduce external stimuli
3. Maintain calm, non-threatening communication
4. Pharmacological options:
   • Benzodiazepines
   • Antipsychotics (oral or intramuscular)
5. Physical restraint if legally justified
6. Avoid antidepressants or stimulants during acute phase

Schizophrenia

Clinical Features

• Positive Symptoms:
  • Hallucinations
  • Delusions
  • Disorganised speech or thought
  • Bizarre or disorganised behaviour
• Negative Symptoms:
  • Blunted affect
  • Anhedonia
  • Poverty of speech or thought
  • Lack of motivation (avolition)
  • Poor concentration
  • Self-neglect (e.g., poor hygiene, forgetting basic tasks)

Risk Factors

• Family history of schizophrenia
• Substance use disorders
• Anxiety or developmental disorders

Pathophysiology

1. Dopamine Hypothesis

• Overactivity in dopaminergic pathways → psychosis
• Linked to:
  • ↑ dopamine release
  • ↑ dopamine receptor (D2R) density
• D2 receptors particularly dense in mesolimbic-mesocortical pathways
• Antipsychotics often act as D2R antagonists, but may also affect other receptors

2. Dysregulation Hypothesis

• Involves broader neurotransmitter disruption beyond dopamine:
  • Serotonin: Modulates dopamine and cognition
  • Glutamate: NMDA receptor dysfunction associated with psychotic symptoms
  • GABA: Deficient inhibitory control (“sensory gating”) may contribute

DSM-5 Diagnostic Criteria – Schizophrenia

A) At least 2 core symptoms for ≥1 month (one must be marked with *):

• *Delusions
• *Hallucinations
• *Disorganised speech
• Grossly disorganised or catatonic behaviour
• Negative symptoms

B) Functional decline in one or more areas (e.g., work, relationships, self-care)

C) Continuous signs of disturbance for ≥6 months, with ≥1 month of active-phase symptoms

D) Exclude schizoaffective and mood disorders if mood symptoms are either absent or present for a minority of total illness duration

E) Exclude substance use and general medical conditions

F) For individuals with autism spectrum disorder or childhood communication disorder: schizophrenia diagnosis requires prominent hallucinations or delusions for ≥1 month

Management

Pharmacological

• Antipsychotics:
  • First-line: Risperidone, olanzapine, haloperidol, paliperidone
  • Refractory cases: Clozapine
• Adjuncts:
  • Mood stabilisers (e.g., lithium, valproate) for mood or aggression
  • Anxiolytics for agitation
  • ECT for severe/refractory psychosis

Psychosocial

• Cognitive Behavioural Therapy (CBT)
• Supportive psychotherapy
• Social skills and vocational rehabilitation
• Community and housing support
• Education on medication adherence and self-care

Summary – Psychosis & Schizophrenia

Psychosis & schizophrenia represent severe disturbances in perception, cognition, and functioning. Schizophrenia is diagnosed when symptoms persist for more than six months, with both positive (hallucinations, delusions) and negative (blunted affect, avolition) symptoms present. Management requires antipsychotic medication and comprehensive psychosocial support. For a broader context, see our Psychiatry & Mental Health Overview page.