Background: In the U.S., 50-75% of nonmedical users of prescription opioids obtain their pills through diversion by friends or relatives. Increasing disposal of unused opioid prescriptions is a fundamental primary prevention strategy in combatting the opioid epidemic.Objectives: To identify interventions for disposal of unused opioid pills and assess the evidence of their effectiveness on disposal-related outcomes.Methods: A search of four electronic databases was conducted (October 2019). We included all empirical studies, systematic literature reviews, and meta-analyses about study medication disposal interventions in the U.S. Studies of disposal interventions that did not include opioids were excluded. We abstracted data for the selected articles to describe the study design, and outcomes. Further, we assessed the quality of each study using the NIH Study Quality Assessment Tools.Results: We identified 25 articles that met our inclusion criteria. None of the 13 studies on drug take-back events or the two studies on donation boxes could draw conclusions about their effectiveness. Although studies on educational interventions found positive effects on knowledge acquisition, they did not find differences in disposal rates. Two randomized controlled trials on drug disposal bags found higher opioid disposal rates in their intervention arms compared to the control arms (57.1% vs 28.6% and 33.3%, p = .01; and 85.7% vs 64.9%, p = .03).Conclusions: Peer-reviewed publications on opioid disposal interventions are limited and either do not address effectiveness or have conflicting findings. Future research should address these limitations and further evaluate implementation and cost-effectiveness.
Keywords: Disposal; Prescription opioid; Systematic review.