Sharing resources to create a district drug formulary: a countywide controlled trial

Creating a drug formulary takes considerable time, but merely adopting one lacks local perspective and ownership. Sharing resources between several practices treads a middle path between these extremes, but is it effective?

The aim of the study was to audit the influence of a district primary care drug formulary on prescribing by general practitioners.

A controlled trial was carried out to compare prescribing by 50 general practitioners from 11 urban and semirural practices in south Bedfordshire that participated in creating a district drug formulary with prescribing by all other general practitioners in the county.

The proportion of prescription items that were for drugs listed in the formulary rose significantly in three therapeutics groups: cardiovascular (by 7-12% above control practice values); musculoskeletal (by 1-11% above control practice values); and obstetrics and gynaecology (by 6-9% above control practice values). The number of items prescribed per prescribing unit fell significantly in three therapeutic groups: musculoskeletal (by 1-7% below control practice values); nervous (by 7-12% below control practice values); and nutrition and blood (by 15-21% below control practice values). The estimated saving resulting from the creation of the formulary was 150,000 pounds (3000 pounds per doctor) per year.

Sharing resources between practices to create a district-wide primary care drug formulary can lead to changes in prescribing and reduce costs sustained over 3 years.