The Substance Abuse and Mental Health Services Administration is launching an experiment with 6300 pharmacies nationwide to educate patients on how to dispose of unused medications.

When patients fill prescriptions for a list of abuse-prone medicines, the pharmacist will also distribute a flyer urging patients to mix unused medication with used cat litter. If patients are not cat owners, they can mix the medication with coffee grounds, dog feces, or even sawdust. The contents should then be sealed in a plastic bag before putting them out for the trash.

The concern, however, pertains to how to dispose of any medication. In the past, patients had been informed that they should flush old drugs down the toilet—a method that is no longer recommended unless the prescription specifically is labeled for flushing.

Unfortunately, "we don't have a silver bullet," commented Joe Starinchak of the US Fish and Wildlife Service. He calls the latest disposal recommendation method interim advice—the top recommendation until further research can determine the best way to balance human health, environmental, and legal issues.