Adherence to BNF Prescribing Standards and PRN Governance in an Early Intervention in Psychosis Service: TwoCycle Clinical Audit
Sita Asi, Yassmine Sabtan, Nandini Chakraborty, Muhammad Ahmed, Dina ElamienAims:
(1) Quantify adherence to British National Formulary (BNF) dose limits; (2) Measure polypharmacy prevalence and rationale documentation; (3) Assess as required (PRN) governance (instruction clarity, review frequency, benzodiazepine duration); and (4) Compare high-dose antipsychotic therapy (HDAT) form completion between cycles.
Methods:
Retrospective analysis of electronic health records (EHR) exported to standardised spreadsheets. Polypharmacy defined as being more than 2 medications of the same class. Doses were expressed as %BNF maximum across six medication classes: >100% denoted high-dose prescribing. PRN indicators captured instruction presence, review status, and benzodiazepine duration ≤4 weeks. Analyses were performed programmatically on two audit cycles.
Results:
BNF adherence worsened: patients exceeding BNF maxima decreased from 1% (Cycle 1) to 2.9% (Cycle 2).
Polypharmacy increased from 5.6% to 10.4% ; (e.g., switching medications/complex illness/patient preference) likely contributed, but the rise suggests persistent clinical complexity.
PRN governance was mixed: “PRN not reviewed” improved from 1.9% to 1.45% , while “PRN instruction missing” rose from 1.1% to 2.1% .
Benzodiazepine PRN >4 weeks increased from 0.26% to 2.70% , indicating a stewardship gap.
HDAT documentation remained suboptimal but improved: 1/378 (0.002%) forms completed in Cycle 1 vs 3/482 (0.62%) in Cycle 2.
Conclusion:
The re-audit demonstrates worsening of BNF dose exceedance and a modest improvement in PRN review , evidencing strengthened prescribing safety processes. Nevertheless, polypharmacy increased, and benzodiazepine PRN durations lengthened, while HDAT form completion remains low. Priorities are: (i) embedding EHR “hard-stops” for >100% BNF doses and missing PRN instructions; (ii) automated four-week PRN benzodiazepine review prompts with default taper plans; (iii) a structured polypharmacy pro-forma recording indication, expected benefit, and review date; and (iv) targeted HDAT training plus mandatory electronic prompts for form completion. A third-cycle re-audit using identical denominators is recommended to verify sustained improvement and close remaining governance gaps