Drug-related problems identified at a Japanese community pharmacy: a cross-sectional study

Objectives: This study aimed to identify drug-related problems (DRPs) using data regarding the communication of pharmacists with prescribers over the phone at a community pharmacy. Furthermore, we elucidated the frequency of the sources of information for detecting each DRP and evaluated the decisions made by the prescribers for each DRP. Methods: This cross-sectional study was conducted at a community pharmacy in Fukuoka Prefecture, Japan. We anonymously collected data obtained by pharmacists through contacting prescribers over the phone relating to any problems or doubts found in prescriptions between April 2016 and March 2019. We classified the data and identified DRPs. We elucidated the frequency of sources of information for detecting each DRP using descriptive analyses and evaluated prescribers' decisions regarding each DRP via multivariate Poisson regression analyses. Key findings: Of the 95 023 prescriptions, 5073 DRPs were identified (5073/95 023 = 5.34%). The most frequent DRP was inappropriate dosage and administration (1349/5073 = 26.59%), followed by non-adherence (1272/5073 = 25.07%) and incorrect prescription periods (889/5073 = 17.52%). Patient interviews were the most frequent sources of information for detecting following DRPs: non-adherence (1057/1272 = 83.10%), untreated indication (590/631 = 93.50%) and adverse drug reactions (80/107 = 74.77%). Most of the DRPs were resolved by making changes to the prescriptions (4571/5073 = 90.10%). Conclusions: Inappropriate dosage and administration and non-adherence issues were the most frequent DRPs in a Japanese community pharmacy. Patient interviews were an important source of information for detecting DRPs. Further research is warranted to address the impact of DRPs on patient safety.