WASHINGTON (AP) — Though they acknowledge the challenge of putting such a mandate in place, Federal health experts say doctors who prescribe painkillers should be required to undergo training aimed at reducing misuse and abuse of the medications.

The group of advisers to the Food and Drug Administration voted unanimously yesterday that the agency should change its risk-management programs for opioid painkillers, highly addictive medications at the center of a national epidemic of addiction and abuse.

Panelists said the risk plans should apply to all prescription painkillers, including immediate-release drugs like Vicodin and Percocet. Currently, the measures only apply to long-acting drugs like OxyContin, which slowly release their ingredients over 12 hours or more.

It’s the second time since 2010 that an FDA panel has recommended expanding painkiller-safety measures and mandating training for doctors. But the training plans instituted about four years ago are voluntary, and FDA figures show that fewer than half of the doctors targeted by the effort have completed the training.