Documenting outpatient problem intervention activities of pharmacists in an HMO

The outpatient drug use review experiences by pharmacists at a large health maintenance organization with on-site pharmacies were investigated. Pharmacists were asked to document the nature of potential drug therapy problems encountered, drug involved, review activities undertaken, and process-outcomes. Patterns of pharmacists intervention were observed over 1 year. Results indicated that the number of problems detected increased substantially during the months immediately following the introduction of problem recording and feedback procedures. During the latter months, the number of prescriptions with problems approximated 4 per 100 dispensed prescriptions. Drug interactions of a moderate nature and drug underuse were the most frequent problem types encountered. Most were not serious and usually resulted in a cautionary or counseling message given to patients by pharmacists. The next most frequently occurring type was drug overuse problems, and, after that, problems concerning some aspect of the prescribing decision. In 9 per cent of all problem interventions and in 44 per cent of prescribing-problem interventions, the outcome of the pharmacist intervention was a change in drug, strength or directions for use. The average amount of pharmacist time per problem intervention varied from 6.0 to 7.8 minutes across problem types. This approximate a pharmacist labor cost of $0.06 per dispensed prescription, given a problem encounter rate of 4 per 100 dispensed prescriptions.