Over the past decade, however, Weber said she’s dramatically cut back on pills by instead using marijuana. “It took care of the pain,” said Weber, executive director of the Colorado chapter of NORML, a national group that backs marijuana legalization.

Spurred partly by stories like Weber’s, policymakers in Colorado, Illinois and New York now allow health professionals to recommend marijuana instead of addictive, potentially deadly pain pills such as OxyContin, Percocet and Vicodin. Forty-six people in the United States die every day from overdoses involving prescription opioids, according to the Centers for Disease Control and Prevention.

New Mexico, New Jersey, New York, and Pennsylvania allow people with opioid addiction to qualify for a medical marijuana card.

But many physicians and medical experts strongly oppose such policies, pointing out that science hasn’t yet shown that dispensary-bought marijuana can deliver the same pain-killing punch as a prescription drug, nor that it can help people kick an opioid addiction.

“We have given marijuana the status of medicine with none of the standards,” said Keith Humphreys, a professor of psychiatry and behavioral sciences at Stanford University. Other medicines, he pointed out, must undergo rigorous clinical trials and win federal approval before being sold to patients.

Health care professionals can’t prescribe pot because the federal government classifies it as an illegal drug. But under 33 state medical marijuana laws, providers can verify that patients suffer from certain conditions, which allows patients to grow pot or buy it from a medical marijuana dispensary.

In states that allow both medical and recreational marijuana, the products are typically regulated separately, sold separately and taxed separately. In Colorado, medical marijuana patients can legally possess more cannabis than other adults, and the pot they buy is cheaper.

Severe or chronic pain are qualifying conditions for a marijuana card in almost all states with a medical marijuana program, according to the Marijuana Policy Project, a Washington, D.C.-based organization that advocates for marijuana legalization. Colorado’s new laws allow doctors and other health professionals with prescribing power to recommend marijuana instead of opioids in all cases, including after minor surgery.

“We’re talking about an alternative to managing symptoms to a narcotic, or to pharmaceutical with severe side effects,” said Colorado Democratic state Rep. Edie Hooton. Her bipartisan bill allowing doctors to recommend pot instead of opioids easily passed the legislature and was signed by Democratic Gov. Jared Polis in May, despite some opposition from the medical establishment.

Dr. Ken Finn, a pain medicine specialist based in Colorado Springs, called the bill “the worst policy I’ve ever seen.” Finn said many of his patients have tried using marijuana to dull their pain, but find it doesn’t help or can’t replace opioids. Their willingness to try an unproven remedy, he said, “tells me what lengths people will go to, to try to get some relief.”

Marijuana as a Painkiller

Nearly 3.1 million medical marijuana patients are registered in the United States and its territories, according to the Marijuana Policy Project.

Many have turned to marijuana because they’re in pain. Over 93% of Colorado’s more than 87,000 medical marijuana patients suffer from severe pain, according to the state Department of Public Health and Environment.

Other people are seeking to ease their pain with recreational pot. Almost two-thirds of a thousand Colorado retail marijuana customers said they used marijuana to relieve pain, according to a survey published in the peer-reviewed Journal of Psychoactive Drugs this year.

Some studies have shown a link between marijuana and pain relief. Many of the about 40 randomized controlled trials that have tested whether cannabis and its chemical compounds, called cannabinoids, reduce chronic pain have found that they work as a pain reliever, said Ziva Cooper, research director of the UCLA Cannabis Research Initiative.

But many of those studies involve discrete or synthetic cannabinoids, rather than the flower, edibles and concentrates sold at dispensaries, she said. For the most part, the studies have been short, looking at cannabis used once or over a few weeks. And they involve patients also taking prescription pain medications.

“We don’t know yet how effective cannabis and cannabinoids are for pain when they’re administered by themselves,” Cooper said. “We also don’t know how cannabis and cannabinoids stack up next to opioids for pain relief.”

Many medical experts say more research is needed. “The science is thin,” said Robert Valuck, executive director of the Colorado Consortium for Prescription Drug Abuse Prevention. Marijuana also can be addictive, he said. “We’re seeing increases in what people call cannabis use disorder.”

As for state laws that allow people addicted to opioids to buy or grow medical marijuana, there’s not strong evidence to suggest that marijuana helps people kick an opioid addiction, Cooper said. “It’s more based on anecdotes — people reporting that they can wean themselves off opioids.”

Even in Colorado — where residents voted to legalize medical marijuana in 2000 and recreational pot in 2012 — many physicians remain reluctant to recommend marijuana. In July, just under 2% of licensed doctors in the state had recommended cannabis to registered medical marijuana patients, according to a Stateline analysis of state data.

It’s not clear whether the new law will convince them to embrace marijuana and move away from prescribing opioids — especially for young people.

“There’s no condition right now where I feel there’s enough information for me to recommend marijuana to a family for a child or an adolescent,” said Dr. Jennifer Hagman, medical director of the eating disorder program at Children’s Hospital Colorado.

Hagman testified against the Colorado bill on behalf of the Colorado Psychiatric Society, the Colorado Child and Adolescent Psychiatric Society, the Colorado Medical Society and the Colorado Chapter of the American Academy of Pediatrics.

She told Stateline she occasionally treats young people experiencing psychosis and depression related to marijuana use. “I know that the vast majority of physicians would very much like to know what specific parts of the marijuana plant, and which kinds, are useful for different conditions — or not,” Hagman said.

Doctors who embrace alternative treatments, such as herbal supplements and acupuncture, tend to be more open to marijuana. Dr. Melissa Milan runs a holistic medicine practice in Colorado and said she’s comfortable recommending marijuana because the overdose risk is negligible. “As a physician, I really want to help people,” she said. “And I want to do no harm.”

People seeking a medical marijuana card also can turn to clinics that specifically employ doctors to issue them.

Many patients are convinced of marijuana’s healing powers. Mindy Mysinger, a 40-year-old former nurse who testified in favor of the Colorado bill, told Stateline that marijuana helped her kick an opioid dependency she developed after multiple back surgeries. At one point, she said, she was taking up to 30 pills a day — a mix of painkillers, pills to address their side effects and over-the-counter drugs.

Mysinger said she decided to reduce her opioid intake after surviving a post-surgery infection. “I realized I had done everything those specialists had said, I took all the pills they told me to take, and I almost died,” she said. Over the past four years, she said, she has adopted a healthier lifestyle and switched from opioids to marijuana. She feels great.

But for many medical professionals, inspirational stories aren’t sufficient proof. “As it relates to pain, the jury is still out,” said Finn, the Colorado Springs doctor. He noted that the placebo effect, or patients’ belief that a certain treatment will make them well, plays a big role in how people experience pain.