Shortly after President Trump declared the overdose epidemic an emergency, it's time for a regular ritual proved to help keep opioids and other drugs out of the wrong hands: Saturday is National Drug Take-Back Day.

The concept is simple: Anytime between 10 a.m. and 2 p.m., bring your old and unneeded prescription medicines to designated drop-off  locations. You'll find dozens of participating police and fire departments, pharmacies, and grocery stores around the Philadelphia region in the U.S. Drug Enforcement Administration's search tool.

Unused drugs left in drawers or medicine chests can tempt experimentation by children and theft by visitors. Pain pills can then be sold on the street, leading to addiction and, occasionally, heroin use. Opioids are responsible for tens of thousands of overdose deaths a year.

The DEA says that throwing old pills in the trash or flushing them down the toilet can be a safety hazard. Medicines dropped off at Saturday's locations, manned by law enforcement officers, are picked up and disposed of by the agency.