What are the indications for Thorazine (chlorpromazine)?

Thorazine (Chlorpromazine) Indications

Chlorpromazine (Thorazine) is primarily indicated for the treatment of schizophrenia, management of psychosis, control of severe nausea and vomiting, treatment of severe behavioral problems in children, and as an adjunct for the relief of intractable hiccups. 1, 2

Primary Psychiatric Indications

• Schizophrenia: Chlorpromazine is effective for treating acute episodes and preventing relapse in schizophrenia, with a recommended therapeutic dose equivalent to 600mg per day 1, 2
• Acute Psychotic Episodes: Regardless of underlying diagnosis, chlorpromazine reduces psychotic symptoms beyond nonspecific sedation 3
• Severe Behavioral Disturbances: Indicated for management of severe agitation and violent behavior, particularly in emergency settings 1

Non-Psychiatric Indications

• Severe Nausea and Vomiting: Effective for treating intractable nausea and vomiting in various clinical scenarios 1
• Intractable Hiccups: Used as an adjunctive treatment for persistent hiccups unresponsive to other interventions 1

Special Populations

• Pediatric Patients: Indicated for severe behavioral problems in children, though careful monitoring is required due to side effect profile 1
• Palliative Care: Used for sedation in management of refractory symptoms at end of life, with starting doses of 12.5mg every 4-12 hours (IV/IM) or 25-100mg every 4-12 hours (rectal) 1

Dosing Considerations

• Schizophrenia Treatment: The minimum effective dose is equivalent to 600mg of chlorpromazine per day 1
• Acute Agitation: For parenteral administration, 12.5mg every 4-12 hours IV/IM or 3-5mg/hour IV 1
• Maintenance Therapy: Usual effective parenteral dose ranges from 37.5-150mg/day 1

Important Monitoring and Side Effects

• QT Prolongation: Chlorpromazine can cause QTc prolongation, potentially resulting in torsades de pointes, requiring ECG monitoring 1
• Extrapyramidal Symptoms: Less likely to cause extrapyramidal symptoms compared to haloperidol, but still significant 4
• Orthostatic Hypotension: More likely to cause hypotension than some other antipsychotics (NNH 7) 1, 4
• Sedation: Significantly sedating (NNH 5), which can be either therapeutic or problematic depending on clinical context 5

Clinical Pitfalls

• Drug Interactions: Avoid co-administration with other QT-prolonging medications, as this increases risk of cardiac arrhythmias 1
• Anticholinergic Effects: Can cause significant anticholinergic side effects, which may worsen conditions with anticholinergic properties 1
• Monitoring Requirements: Regular assessment of cardiovascular status, extrapyramidal symptoms, and metabolic parameters is essential 1
• Treatment Resistance: In treatment-resistant schizophrenia, chlorpromazine is not the preferred agent; clozapine should be considered after failure of at least two adequate antipsychotic trials 1

Comparative Efficacy

• Versus Atypical Antipsychotics: Chlorpromazine causes more extrapyramidal side effects than atypical antipsychotics like quetiapine (RR 8.03) 6
• Versus Haloperidol: Chlorpromazine causes fewer movement disorders but more hypotension compared to haloperidol 4
• Versus Placebo: Significantly reduces relapse rates in schizophrenia compared to placebo (RR 0.57), with NNT of 4 for long-term treatment 5