Background: Unused medications (UM) are an important issue, with the waste associated with UM a burden to the health-care system. The aims of this study were to clarify the amount and costs of UM in patients with advanced cancer at the time of their last admission to a palliative care unit and to explore the factors contributing to the cost of UM and how patients dealt with UM. Methods: A prospective observational study was conducted in single palliative care unit. Unused medications were classified into 6 categories and the number and cost of UM by category calculated per patient. Patients were classified into 2 cost groups (high and low) based on the total cost of UM, and the number and cost of UM by category were compared between these 2 groups. Results: Of 194 consecutive hospitalized patients, data were analyzed for 90. The mean number and cost of UM per patient was 440 and US$301, respectively. Opioids accounted for 47% of the cost of UM. Comparing costs by UM category, the proportion of opioids (51% vs 21%; P < .0001) and oral anticancer drugs (14% vs 3%; P = .02) was higher in the high- than in the low-cost group. Conclusion: Based on the results of the present study, the estimated annual waste cost of UM for patients with cancer who died in Japan was approximately US$110 million. Interventions to educate patients regarding UM and to eliminate barriers to opioid use may help reduce the cost of UM, particularly opioids and anticancer drugs.
Opioid use and effectiveness of its prescription at discharge in an acute pain relief and palliative care unit