A 28-year-old man presents with acute-onset psychosis, disorganized speech, and auditory hallucinations. He has no prior psychiatric history and no medical comorbidities. Which antipsychotic is the first-line drug of choice for his acute psychotic episode?

Explanation

## First-Line Antipsychotic in Acute Psychosis **Key Point:** Risperidone is the preferred first-line atypical antipsychotic for acute psychotic episodes in drug-naïve patients without medical contraindications. ### Why Risperidone? **High-Yield:** Risperidone offers the optimal balance of: - Rapid onset of action (efficacy within 2–4 weeks) - Broad-spectrum efficacy (positive and negative symptoms) - Lower risk of extrapyramidal side effects (EPS) compared to typical antipsychotics - Acceptable metabolic profile at standard doses (5–6 mg/day) - Oral and IM formulations available for flexibility ### Comparison with Other Options | Feature | Risperidone | Haloperidol | Chlorpromazine | Clozapine | |---------|-------------|-------------|-----------------|----------| | **Generation** | Atypical (2nd) | Typical (1st) | Typical (1st) | Atypical (2nd) | | **EPS Risk** | Low–moderate | Very high | Moderate | Very low | | **Onset** | 2–4 weeks | 2–4 weeks | 2–4 weeks | 4–6 weeks | | **First-line?** | **Yes** | No (outdated) | No (outdated) | No (reserved) | | **Metabolic** | Mild weight gain | Minimal | Significant | Significant | | **Indication** | Acute psychosis | Acute agitation only | Acute psychosis (historical) | Treatment-resistant only | **Clinical Pearl:** Haloperidol is now reserved for acute behavioral emergencies (severe agitation, violence) in hospital settings, NOT routine first-line psychosis management. Typical antipsychotics carry unacceptable EPS burden in modern practice. **Mnemonic — Atypical Antipsychotics (RACE):** Risperidone, Aripiprazole, Clozapine, Eosinophilia (olanzapine). Risperidone is the most commonly used first-line agent. ### Why Not Clozapine? Clozapine is reserved for **treatment-resistant schizophrenia** (failure of ≥2 antipsychotics at adequate doses/duration). It requires: - Baseline and regular white blood cell (WBC) monitoring (risk of agranulocytosis) - Complex titration protocol - Higher cost - Use only after first-line agents fail. [cite:KD Tripathi 8e Ch 12]