Evaluation of the introduction of an antimicrobial drugs formulary in a general hospital in Slovenia

Objective: To analyse the consumption of antimicrobials in a general hospital prior and after implementation of a drug formulary and the economic evaluation of the implementation.Method: Data were obtained from medical documentation collected over a one-month period for all in-patients in four major hospital departments prior to and after the implementation of a drug formulary. The ATC/DDD methodology was used to analyse consumption of antimicrobials. Patients were grouped in therapeutic groups according to their disease and the clinical and economic outcome of the implemented intervention was estimated. Retrospectively, pharmacoeconomical cost–effectiveness analysis was undertaken from the hospitals point of view.Results: The overall use of antimicrobials after implementation in DDD/100 bed-days increased by 16.8%. However, the drug formulary was successfully implemented in 1999, saving 33.7% DDD/100 bed-days of antimicrobials restricted by the formulary. At the same time, treatment time was shortened by 26.5%, with an overall saving of 35.1% per patient.Conclusions: The importance of a drug formulary for antimicrobials was demonstrated in terms of its clinical and economic outcome. A practical case of co-operation between physicians and clinical pharmacists in such a project was also revealed.