Hospital drug therapy cost containment through a preferred medicines list and drug utilisation review system.

AIM: To measure the economic impact of the introduction of a preferred medicines list and drug utilisation review process on drug therapy costs at the six Christchurch hospitals in the Canterbury Area Health Board.
METHODS: The preferred medicines list, a consensus derived recommended drug list, was introduced along with a drug utilisation review process in December 1990. Detailed drug therapy costs were collected from the pharmacy computer for the 1990/1 and 1991/2 hospital financial years. Data was analysed under the 15 British National Formulary drug groups and also 14 other categories. National hospital drug costs based on sales to hospitals and local drug cost trends prior to the preferred medicine list system introduction were used as baseline measures. Hospital patient discharge numbers and patient days were also recorded.
RESULTS: Prior to the preferred medicines list introduction local drug therapy costs had been rising on average 30% per year. Between 1990/1 and 1991/2 total drug costs fell by 2% from $12.16M to $11.86M while nationally, drug sales to hospitals increased by 15%. Included in the local expenditure were drugs external to the preferred medicine list/drug utilisation review system whose costs are reimbursed to the area health board. When these costs were deducted, inpatient drug costs fell by 11% from $8.76M to $7.7M. In the 29 categories reviewed, 17 had decreases, while the remaining areas increased. Total patient numbers during the period increased by 3% while total patient days decreased by 10%.
CONCLUSION: The preferred medicines list and the associated drug utilisation review process played a major role in the reduction of inpatient drug therapy costs at the Christchurch hospitals. Other factors such as cost shifting or changes in community drug use may have also been responsible for some of the savings.