Antipsychotic Dose Equivalence Calculator

Converts daily doses of various antipsychotics into chlorpromazine equivalent doses (CPZeq) using either the classical Davis (1974) method or the more recent consensus-based Bazire / Maudsley method. Equivalence tables are approximate and should guide rather than dictate dosing.

mg

Note: The equivalence factor for aripiprazole is particularly variable across sources (range 5-7.5 mg = 100 mg chlorpromazine). Use the most conservative estimate when switching.

References

  1. Chlorpromazine equivalent doses for the newer atypical antipsychotics. Journal of Clinical Psychiatry (2004). https://pubmed.ncbi.nlm.nih.gov/15037108/
  2. International consensus study of antipsychotic dosing. American Journal of Psychiatry (2010). https://pubmed.ncbi.nlm.nih.gov/20123909/
  3. Maudsley Prescribing Guidelines in Psychiatry. Wiley / Taylor & Francis (2023). https://www.wiley.com/en-us/The+Maudsley+Prescribing+Guidelines+in+Psychiatry%2C+14th+Edition-p-9781119855138
Medical Disclaimer

This calculator is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare provider with any questions you may have regarding a medical condition.

  • Dose equivalence is an approximation; clinical response and side-effect profiles vary between agents and individuals.
  • Davis (1974) is based on older first-generation antipsychotics and may overestimate or underestimate newer agents.
  • Bazire / Maudsley consensus values are more contemporary but still vary between sources.
  • Switching antipsychotics based solely on CPZeq can lead to relapse or side effects; always consider cross-tapering.