What is the maximum dose of Chlorpromazine (Chlorpromazine), a typical antipsychotic medication?

From the Guidelines

The maximum dose of chlorpromazine should not exceed 1000 mg per day, with a recommended minimum daily dose equivalent to 600mg of chlorpromazine per day for therapeutic effectiveness in treatment-resistant schizophrenia, as suggested by the treatment response and resistance in psychosis (TRRIP) working group consensus guidelines 1. When determining the appropriate dose, it's crucial to consider the individual patient's response and tolerability, aiming for the lowest effective dose to minimize side effects.

• Key considerations include:
  • Starting with lower doses, such as 25-100 mg, and gradually increasing as needed and tolerated.
  • Elderly patients requiring lower maximum doses, generally not exceeding 300 mg daily, due to increased sensitivity to side effects.
  • The risk of side effects, including sedation, orthostatic hypotension, anticholinergic effects, extrapyramidal symptoms, and potentially QT prolongation, which increases with higher doses.
• In clinical practice, the dose of chlorpromazine must be individualized, taking into account the specific condition being treated, the patient's age, and their ability to tolerate the medication, as indicated by the summary of product characteristics mentioned in the study by Howes et al. 1.
• For acute settings, such as severe agitation, intramuscular administration may be used, but with careful consideration of the maximum single doses and the total daily dose to avoid exceeding the recommended maximum of 1000 mg per day, as guided by established conversion ratios and consensus guidelines 1.

From the Research

Chlorpromazine Doses

• The maximum dose of chlorpromazine is not explicitly stated in the provided studies, but the studies mention various dose ranges:
  • Low-dose: ≤ 400 mg/day 2
  • Medium-dose: 401 mg/day to 800 mg/day 2
  • High-dose: > 800 mg/day 2
  • Specific doses: 200-800 mg/d 3, 100-400 mg 4, 1200 mg/day 5

Comparison of Chlorpromazine Doses

• A study comparing low-dose (≤ 400 mg/day) and medium-dose (401 mg/day to 800 mg/day) chlorpromazine found no clear benefit of one dose over the other for global and mental state outcomes 2
• Another study comparing low-dose (≤ 400 mg/day) and high-dose (> 800 mg/day) chlorpromazine found that the high-dose group had a greater risk of extrapyramidal symptoms and more people leaving the study due to deterioration in behavior 2

Comparison with Other Antipsychotics

• A study comparing chlorpromazine with haloperidol found that haloperidol was associated with fewer people leaving the study early, but chlorpromazine was associated with fewer movement disorders 6
• A study comparing olanzapine with chlorpromazine found that olanzapine was more efficacious and had a more favorable tolerability profile 3
• A study comparing clozapine, haloperidol, and chlorpromazine found that clozapine was more effective and had fewer adverse effects than haloperidol and chlorpromazine 4