Rationalising Antipsychotic Polypharmacy: A Cross-sectional, Pre- and Post-intervention Comparative Study

Area of Science:

• Pharmacology
• Clinical Pharmacy
• Psychiatry

Background:

• Antipsychotic polypharmacy (APP), the use of multiple antipsychotics, is common in schizophrenia treatment despite risks.
• Guideline adherence in APP is often hindered by a lack of documented prescribing rationale.
• A pharmacist-led intervention aimed to improve documentation and rationalization of APP.

Purpose of the Study:

• To assess the impact of a pharmacist-led intervention on APP prevalence and prescribing burden.
• To evaluate changes in the documentation rate of prescribing reasons for APP.
• To determine the effect on the adherence to treatment guidelines for APP.

Main Methods:

• Retrospective, cross-sectional medical record audit comparing pre- and post-intervention periods.
• Quantified APP prevalence, prescribing burden (defined daily doses and maximum licensed daily doses).
• Assessed documented prescribing reasons against clinical guidelines.

Main Results:

• APP prevalence remained unchanged (39.1% vs 39.0%).
• Prescribing burden (mean DDD and MLDD) showed no significant difference between periods.
• Documentation of prescribing reasons significantly increased post-intervention (68.0% vs 36.7%), though guideline adherence remained similar (58.8% vs 54.5%).

Conclusions:

• The intervention successfully improved the documentation of reasons for antipsychotic polypharmacy.
• While prevalence and guideline adherence were unaffected, improved documentation aids informed prescribing decisions.
• Pharmacist involvement is crucial in bridging communication gaps and optimizing APP rationalization.