Potential drug-related problems detected by routine pharmaceutical interventions: safety and economic contributions made by hospital pharmacists in Japan

BACKGROUND: Pharmaceutical intervention enables safe and effective pharmacotherapy by avoiding of adverse drug reactions (ADRs) and efficacy attenuations. Many prescriptions require optimization, and pharmaceutical interventions are inextricably associated with the prevention of potential drug-related problems (DRPs). Although the analysis and understanding of pharmaceutical interventions can lead to improvement in prescription, the analysis of routine pharmaceutical interventions in Japan in insufficient. Thus, we conducted this study to understand potential DRPs by analyzing routine pharmaceutical interventions made by pharmacists in Japan. METHODS: Pharmacists register the details of pharmaceutical interventions (excluding personal patient information) in a web-based database. We classified data of pharmaceutical interventions into 13 DRP types, 43 DRP subtypes, and 10 intervention categories (e.g., avoidance of serious ADRs and renal dosing recommendations). These data were analyzed with a focus on renal dysfunction and polypharmacy. RESULTS: During the study period, 2376 pharmaceutical interventions were performed. Overall, 68.2% of pharmaceutical interventions were for patients aged over 65 years. The most frequently detected potential DRP was overdosage, followed by omission of prescription, contraindications, and duplication of a drug with similar effect. The main cause of contraindication and overdosage was renal function deterioration, and that of polypharmacy was duplication of a drug with similar effect. Using our original evidence-based approach, we found that 2376 pharmaceutical interventions prevented ADRs for 1678 drugs, with potential cost savings of up to USD 2,657,820. CONCLUSIONS: Our results indicate that the analysis of routine pharmaceutical interventions is beneficial for detecting potential DRPs. Our findings also show that, in an aging society, pharmacists have an important role in providing medication safety, with potential cost savings.