Health officials say they're clamping down on excessive prescriptions for opioids in the state's Medicaid program — part of a larger effort to curb runaway addiction that often begins with painkillers.

Under a policy that goes into effect in July, doctors in the program that serves one in five Marylanders will need prior authorization to write some prescriptions for the drugs.

The move is the latest effort by the state Department of Health and Mental Hygiene to address record overdose deaths that have hit Medicaid recipients disproportionately. Officials want to grab the attention of doctors before their patients are too deep in the throes of addiction to opioids, which include prescription drugs such as oxycodone and morphine as well as illicit heroin and fentanyl.

“We really want doctors to stop and think before they prescribe,” said Shannon McMahon, deputy health secretary for health care financing. “We're using payment policy to drive the outcomes we're hoping to get.”

Dr. Leana Wen, Baltimore's health commissioner, called the move “an important step in a time of a public health epidemic.”

Opioid addiction has hit the city especially hard. About a third of drug and alcohol overdose deaths reported in Maryland for 2016 so far were logged in Baltimore.

Patients on Medicaid, the federal-state health insurance program for the poor, represent about 20 percent of Maryland's population, but accounted for 55 percent of all drug- and alcohol-related fatal overdoses in 2015, according to state data.

McMahon said officials hoped doctors would be aware of risks from opioids to all of their patients, not just those on Medicaid.

With the new rules, officials want doctors to consider alternative painkillers, start with low doses, and better screen patients for abuse or risk. They are also encouraging doctors to refer more addicted patients to treatment and ensure they keep the overdose antidote naloxone on hand.

McMahon said doctors who don't follow guidelines from the U.S. Centers for Disease Control and Prevention will be required to seek prior authorization before prescribing opioids.

The guidelines, released last year, outline when it's appropriate to begin or continue use of the drugs for chronic pain, which is pain that lasts longer than three months; how big a dose to prescribe and for how long; and how to assess the risk of abuse.

CDC officials wrote the guidelines in response to a flood of prescriptions written by doctors in recent years. The federal agency said enough prescriptions were being written by 2012 to supply every American adult with a bottle of pills.

McMahon said it's not clear whether the CDC guidelines have yet influenced doctors' prescribing habits in Maryland, but the new rule should slow or deter the liberal prescription of opioids.

She couldn't say how many doctors would need the prior authorization. She said the health department was working on a way to monitor them.

State data show that more than 7.3 million prescriptions for controlled substances were written in the first 10 months of 2016, down just slightly from the same period the year before.

Opioids were linked to the bulk of the 1,468 drug- and alcohol-related overdose deaths in the first nine months of 2016, the latest data available.

Officials have taken other steps in response to opioid misuse. They have expanded access to residential treatment for addicted Medicaid enrollees and accelerated enrollment in treatment for ex-offenders, who suffer high rates of substance abuse.

Wen, an emergency physician, said the requirement for prior authorization will encourage doctors to consider other medications and start with low doses of opioids when necessary to control pain.

“It's true that medical culture is entrenched and often difficult to change,” she said. “It's what we learned in medical school and our residency training. We just wrote prescriptions for pain, and risk was never part of the conversation.”

But she said attitudes around prescribing opioids are changing.

Gene M. Ransom III, CEO of MedChi, the state medical society, said state Medicaid officials have been working with the group to ensure that the rules are in keeping with standards of care and are not too onerous.

Doctors don't usually embrace requirements for prior authorization, Ransom said. But in this case, he said, they understand the size of the opioid abuse problem and “want to be part of the solution.”

There might not be much need to seek authorization if doctors fully understand and comply with the CDC guidelines for prescribing.

The challenge will be educating doctors before July, when all of Maryland's thousands of doctors will be required to register for the state's prescription drug monitoring program. That's a computer system that keeps track of all prescriptions so doctors can tell when patients are collecting multiple scripts.

Dr. Tiffany Wedlake, a Medicaid adviser, said all of the managed-care organizations that serve patients in Maryland signed on to the changes. She said officials understand they are imposing change through regulations, and they will need to ensure everyone is up to speed.

“We're trying to educate the general provider community,” she said. “We're hoping they understand this is happening for the right reasons.”