Proper disposal of leftover medication, particularly antibiotics and opioids, can help reduce antibiotic resistance, prevent children from being poisoned and stop the misuse of addiction-forming drugs. But a telephone survey conducted by researchers at UC San Francisco found that fewer than half of California pharmacies provided disposal instructions meeting U.S. Food and Drug Administration guidelines, and just 10 percent followed the FDA's preferred recommendation to take back unused medications from their customers.

Over a two-month period in early 2018 researchers posing as parents of children who had recently had surgery spoke to employees at nearly 900 pharmacies in California and asked them what to do with two leftover medications: the antibiotic Bactrim (sulfamethoxazole-trimethoprim), and liquid Hycet (hydrocodone-acetaminophen), a pain reliever containing an opioid compound.

Neither medication should be left in the medicine cabinet, since the antibiotics could be taken improperly for subsequent infections they cannot cure, contributing to antibiotic resistance, and opioids can fall into the wrong hands.

In the absence of a takeback program, the FDA says antibiotics should be mixed with an unpalatable substance, such as coffee grounds or kitty litter, and disposed of in a sealed container in the trash to keep them from getting into the water supply or inadvertently ingested. The FDA recommends that opioids be flushed down a toilet, since people may otherwise find and accidentally ingest or intentionally abuse them, even when they've been mixed with an unpalatable substance and thrown into the trash.

Overall, just 47 percent of pharmacies gave the correct instructions on how to dispose of antibiotics, and only 34 percent gave correct instructions for opioids.

"This clearly points to the need for better dissemination of information on proper medication disposal," said Hillary Copp, an associate professor of urology at UCSF and the senior author of the study, published Monday, Dec. 30, 2019, in Annals of Internal Medicine. "The FDA has specific instructions on how to dispose of these medications, and the American Pharmacists Association has adopted this as their standard. Yet it's not being given to the consumer correctly the majority of the time."

Copp stressed that improving disposal practices will require both better efforts to educate patients, and those who advise them, as well as expanded disposal programs to ensure that patients have a place to take unused medication. At UCSF, Copp said, physicians are working to uniformly incorporate disposal instructions into the information that patients receive when they are discharged.

"A pharmacy is a place where medications are dispensed so it is natural for people to look to this same location for advice on how to dispose of unused medications," Copp said. However, she added, "pharmacies should not be solely responsible for providing proper disposal information. Managing leftover medications is a complex problem that should be addressed from multiple angles."

Rachel E Selekman, Thomas W Gaither, Zachary Kornberg, Aron Liaw, Hillary L Copp.
Unwanted Medication Disposal: Audit of California Pharmacy Advice.
Ann Intern Med. 2019. doi: 10.7326/M19-2409.