Antipsychotic prescribing patterns in a Tasmanian mental health inpatient unit (MHIU): Primary findings and comparison with RANZCP guidelines for schizophrenia and bipolar affective disorder (BPAD)

Abstract

Objective

This study analysed antipsychotic prescribing patterns at discharge from an acute Tasmanian MHIU, and evaluated prescribing practice alignment with RANZCP clinical practice guidelines (CPG) for schizophrenia and BPAD.

Methods

Descriptive cross-sectional analysis of discharge prescriptions was conducted for 202 patients extracted from routinely collected data. Diagnoses, prescribed antipsychotics, and doses (converted to olanzapine equivalents) were reviewed. Polypharmacy, as well as the use of depot and PRN doses, were also analysed.

Results

Overall, 66% of patients were prescribed antipsychotics at discharge, with 33% of this group receiving polypharmacy. Schizophrenia was the most common indication (35%), followed by off-label prescriptions (34%) and mood disorders (20%). Quetiapine IR and olanzapine were the most prescribed, with high rates of off-label use and polypharmacy. In around 10% of patients, doses exceeded 20 mg/day olanzapine equivalents. Depot formulations were prescribed to 24% of patients, with aripiprazole being most common. Schizophrenia spectrum diagnoses were significantly associated with polypharmacy.

Conclusions

This study highlights high rates of antipsychotic off-label prescribing and polypharmacy. The findings underscore the need for individualized prescribing, enhanced monitoring, and regular medication reviews. They also raise questions about the applicability of CPGs. Further research should investigate factors influencing off-label prescribing and strategies for safer prescribing.