Type and Frequency of Opioid Pain Medications Returned for Disposal.

Prescription opioids have increasingly been involved in overdose deaths and treatment admissions. Disposal programs may play an important role in curbing this trend. The objectives of this study were to: (1) quantify the prescription opioids returned for disposal to a local take-back program, and (2) explore selected drug characteristics that may predict the quantity of unused opioids. Leftover prescription opioid medications returned for disposal to a community drug take-back event were quantified and analyzed according to controlled substances schedule, formulation, number of active ingredients, and directions for use. Days' supply of medication remaining, calculated using the number of dosage units remaining divided by the maximum number of dosage units per day allowed by the prescriber, was the primary outcome variable. Opioid prescriptions returned for disposal had greater than 60 % of the amount dispensed remaining unused. Short-acting C-II and C-III combination opioids accounted for greater than 80 % of the prescriptions returned. Day supply dispensed was the strongest predictor of day supply remaining, regardless of other drug characteristics. These findings indicate that disposal programs are effective at removing unused medication from patient homes. To reduce leftover medication, prescriber education programs should address the amount to be prescribed. Continual monitoring of quantities prescribed and returned for disposal may be useful in evaluating the effects of these programs on leftover medication. Further research on drug characteristics may inform prescribing practices and reduce leftover medication.