We used the Safe Kids NC Operation Medicine Drop event registration system and program documents to review and validate the number of events, the counties where events were held, and the number of unit doses (pills) collected for the period March 2010 to June 2014. We used unit dose—that is, the number of pills collected—as the general outcome measure. When final collection data were reported in pounds, we converted to unit dose (number of pills) using a standard law enforcement convention of 1 pound equal to 750 pills (Donnie R. Varnell, North Carolina State Bureau of Investigation, Diversion and Environmental Crimes Unit; written communication; April 8, 2015).

The University of North Carolina Injury Prevention Research Center downloaded a complete file of take-back events from the Safe Kids NC database, cleaned and analyzed the data, and confirmed results with documentation from the SBI. We used SAS version 9.4 to generate basic counts and frequencies of outcome variables, and we used ArcGIS version 10.0 to create the map.

From March 2010 to June 2014, Operation Medicine Drop held 1,395 events with 245 different participating law enforcement agencies in 91 of the state’s 100 counties, and these events collected 69.6 million unit doses. More than 60 local Safe Kids NC community coalitions had participated as of June 2014. From March 2010 to June 2014, there was a 35.8% increase in the number of participating counties and a 597% increase in the number of participating law enforcement agencies.

Over the course of 5 years, Operation Medicine Drop collected 69.6 million doses of unwanted drugs. These numbers exceed reports in the media from fall take-back events in other states, which reported collecting between 500 and 1,000 lbs [9–12]. Despite collecting 69.6 million unit doses of medications (with considerable commitment and enthusiasm at the local level), drug take-back events face barriers that may prevent communities from hosting these events. The Controlled Substances Act requires the participation of law enforcement in drug take-back events to prevent possible diversion. In addition, pharmacists or pharmacy technicians are needed to identify and verify controlled substances and other drugs of concern.

Cost is another major barrier that potentially limits whether community-based groups can maintain these efforts. It costs $1.25 per pound to incinerate unwanted drugs. For events held on September 27, 2014, for example, North Carolina collected 10,800 lbs of drugs, and the cost for incineration alone was estimated at $13,500. For the Operation Medicine Drop events reported here, only EPA-approved incinerators for biohazardous materials were allowed to be used. North Carolina has only one EPA-approved incinerator. In June 2013, when that incinerator was temporarily shut down, medications were shipped to Alabama for destruction, with DEA paying the additional cost of transporting the items to Alabama. Community and state programs engaging in drug take-back efforts must consider the costs associated with maintaining this kind of operation and providing the necessary oversight and approvals.

In its final rule regarding the disposal of pharmaceutical controlled substances, DEA did not require a particular method of destruction “so long as the desired result is achieved” and the method is secure, convenient, and responsible, “consistent with preventing the diversion of such substances” [13]. The rule, which went into effect on October 9, 2014, allows participating pharmacies, long-term care facilities, hospitals, and pharmaceutical companies to take back unused prescription medications. Prior to the implementation of this rule, only law enforcement agencies were allowed to collect drugs. It is unclear whether pharmacies, narcotics treatment programs, hospitals, and clinics will establish take-back programs, but this ruling suggests that Operation Medicine Drop may have more options for disposing of collected medicines or could partner with state law enforcement agencies to pursue more cost-effective and convenient means of disposal. In the meantime, Operation Medicine Drop staff members hope to continue events into the future.

The expansion of Operation Medicine Drop to include permanent drop-off boxes could dramatically change individuals’ ability to discard unused medications. Operation Medicine Drop is working with various programs—including Community Care of North Carolina’s Project Lazarus, a statewide overdose prevention program—to place permanent drop boxes in every county. Housed in law enforcement offices, these drop boxes would be more accessible to people than the Operation Medicine Drop events, which operate on a limited schedule. However, anecdotal evidence suggests that some community members might not be as willing to take unused medications and drugs to law enforcement agencies. Currently, according to the SBI, most drop boxes average approximately 12–15 lbs of collected medications per week.

Our efforts to measure the impact of Operation Medicine Drop are limited by the electronic system that is currently in place. In this system, groups organizing take-back events are only asked to record the quantity of pills collected. Thus there is no way to divide the total collection by drug class. With increased funding, Operation Medicine Drop could potentially hire pharmacists to classify the drugs collected.

Second, we are limited in our ability to explore the causal relationship between Operation Medicine Drop’s take-back events and the number of drug poisoning deaths in the counties where Operation Medicine Drop has held events. Currently, we are only able to describe what Operation Medicine Drop has done in bringing partners together to collect and safely destroy unwanted prescription drugs. With more robust data collection and evaluation measures, perhaps, we could describe the overall impact on public health.

Finally, our analysis is limited by the data reported to DEA. Individual weights for the drugs collected at each police department or sheriff’s office are not reported. Instead, DEA only receives a total weight, which limited our ability to account for all drugs that had been dropped off in each county in the fall 2014 take-back events.

Despite limited resources, Safe Kids NC has organized a statewide drug disposal collection program that has resulted in more than 69 million doses of medications being taken out of circulation. Thus, Operation Medicine Drop has been successful in safely disposing of unwanted prescription drugs. While we cannot say what proportion of those drugs are controlled substances that are partially responsible for the epidemic of overdose deaths in this state, Operation Medicine Drop has helped to communicate the message that safely disposing of unwanted, unused, and/or expired medications is key to keeping children safe.