Pain drugs will need new warnings to alert patients and doctors about their dangers.

Each year, 16,000 people die of overdoses that include prescription opioids— and the extended-release and long-acting drugs such as Oxycontin or methadone are disproportionately responsible for such deaths. While currently labeled to treat moderate to severe pain, the drugs will now carry warnings that indicate the drugs are to be used only “for the management of pain severe enough to require daily, around-the-clock opioid treatment and for which alternative treatments are inadequate.” New warnings about the withdrawal syndrome that can affect newborns exposed during pregnancy, which can be life-threatening if not managed properly, will also be included.

The Food and Drug Administration’s (FDA) action is in response to the growing number of overdose and abuse cases related to opioid use; by restricting approval to the most severe cases of pain, the agency hopes to limit access to the drugs, since more prescriptions can lead to wider usage and to dependence or addiction. “The FDA is invoking its authority to require safety labeling changes and postmarket studies to combat the crisis of misuse, abuse, addiction, overdose, and death from these potent drugs that have harmed too many patients and devastated too many families and communities,” FDA commissioner Dr. Margaret Hamburg said in a statement.

While a citizen’s petition by a group called Physicians for Responsible Opioid Prescribing (PROP), had called for limiting the drugs’ use to 90 days or less, the agency rejected that idea. “What we’ve concluded is that we need more information about where risk begins,” said Dr. Douglas Throckmorton, the deputy director of regulatory programs at the FDA at a press conference, explaining that existing data doesn’t suggest a particular dose or duration at which risk becomes problematic. The FDA is also requiring that manufacturers conduct post-marketing studies to try to answer these questions.

“I would hope that [the new label] would help improve careful appropriate prescribing of these medications, which have unquestioned value in appropriately chosen patients,” Throckmorton said.