(AP/Toby Talbot)

The Food and Drug Administration, which has been criticized as too willing to approve addictive narcotic painkillers and too slow to fight their abuse and overuse, said Thursday that it will overhaul policies addressing the powerful class of drugs.

The announcement comes amid an epidemic of prescription drug and heroin overdoses, which now kill more Americans each year than automobile accidents. The problem has become a key issue in the presidential campaign and among lawmakers on Capitol Hill, where at least one U.S. senator -- Edward Markey of Massachusetts -- has vowed to block the confirmation of President Obama's nominee to lead the FDA until the agency takes greater action.

"We're not doing this directly because of Sen. Markey," Robert Califf, the currently stalled nominee, told reporters in a call. But, he added, "It's fair to say we heard what Congress had to say. ... They are reflecting the concerns of the American people."

Califf said the changes followed an assessment in which agency officials agreed that "we can do more" to combat the public health crises stemming from opioid and heroin abuse.

The FDA plans to convene an outside advisory committee to seek advice before approving any new opioid medication that does not have "abuse-deterrent" properties. It also will convene a separate pediatric advisory committee to examine any proposed labeling changes that relate to children; last year, the FDA approved the use of OxyContin in children as young as 11 without seeking such input.

Officials said they will strengthen follow-up studies to provide more insight about the safety and effectiveness of opioids' long-term use and, in an effort to curb over-prescribing, will aim to increase the number of doctors who receive training about them. In addition, the agency will encourage development of more painkillers that are difficult to crush, break or dissolve -- common tactics for people trying to ingest large amounts quickly by snorting or injecting a drug. And it will try to widen access to treatments such as naloxone, a drug that can quickly counteract the effects of heroin or opioid overdose.

Andrew Kolodny, director of Physicians for Responsible Opioid Prescribing and a frequent critic of the FDA's response to the opioid epidemic, doubts the agency's proposed changes will have much impact.

"I think the key driver behind FDA’s announcement is public relations," Kolodny said in an email. "They’ve been getting beat up for their opioid decisions -- with good reason."

Kolodny said the agency should hold advisory meetings for all opioid-related decisions, not just for new drugs that lack abuse-deterrent properties. While glad the agency plans to strengthen warning labels on immediate-release opioids, he said he doubts its moves will be specific and aggressive enough to meaningfully alter prescribing habits. But if the FDA truly changes its risk-benefit analysis when considering the powerful painkillers, that could prove significant, he said. "But that's a big if."

In a statement Thursday, Markey called the agency's proposed changes "a good start," but said it needed to go further and hold public advisory committee hearings around any kind of opioid approval decision. Until the agency commits to doing that, he said, "I will continue my hold on Dr. Califf's nomination."

The Centers for Disease Control and Prevention reported recently that the 28,647 deaths from prescription opioids and heroin in 2014 were a record. The agency said that more than six in 10 drug overdose deaths were caused by opioids that year.

West Virginia, New Mexico, New Hampshire, Kentucky and Ohio had the highest rates of drug overdose deaths per 100,000 people in 2014. North Dakota, New Hampshire, Maine, New Mexico and Alabama saw the largest increases in their death rates.

In recent years, government officials at the federal, state and local levels have devoted new resources to cracking down on illegal drug trafficking and, more broadly, to distributing naloxone. The Obama administration announced new "public health-public safety partnerships" in areas plagued by drug overdoses, moved to increase access to treatment and took steps to better train doctors who prescribe prescription painkillers. This week, the White House proposed more than $1 billion in new spending for an array of federal and state programs to offer expanded access to treatment for the millions of Americans hooked on opioid painkillers and heroin.

The FDA itself has been faulted. Its approval last year of OxyContin -- an extended-release form of the painkiller oxycodone -- for certain pediatric use was welcomed by some pediatricians and pain specialists but provoked anger on social media and among some lawmakers. Though the agency restricted the drug to children 11 and older who need “daily, round-the-clock, long-term” relief from pain that can’t be treated adequately with other medications, critics accused it of acting irresponsibly.

Sen. Joe Manchin III (D-W.Va.), whose state has been especially hard hit by the epidemic of prescription drug and heroin abuse, wrote a scathing letter telling the FDA it “should be absolutely ashamed of itself for this reckless act.” Like Markey, Manchin has threatened to hold up Califf's nomination.

Democratic presidential candidate Hillary Clinton called the decision "absolutely incomprehensible."

The FDA, in its defense, said the drug's approval wasn’t intended to expand the use opioids in children but to instead give doctors better guidelines about how to use OxyContin safely in pediatric patients. Doctors can already prescribe medications any way they see fit, and many physicians have long given potent painkillers “off label” to children suffering from cancer, major surgeries or other trauma, the agency said.

This post has been updated. 

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