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Why Elizabeth Warren thinks legalizing marijuana could help end America’s opioid addiction crisis

Sen. Elizabeth Warren (D-Mass.) addresses the 10th annual Make Progress National Summit last July in Washington. (Chip Somodevilla/Getty Images)

Sen. Elizabeth Warren wants the Centers for Disease Control and Prevention to explore the use of medical marijuana as an alternative to the powerful opioid painkillers that kill thousands of people each year.

In a letter to CDC chief Tom Friedan, the Massachusetts Democrat also asks the agency to look into “the impact of the legalization of medical and recreational marijuana on opioid overdose deaths.”

From a public health standpoint, Warren is right. There is a lot of potential here. Here’s a rundown of what the research has shown so far:

Marijuana is effective at treating pain

A big meta-analysis of 79 studies in the Journal of the American Medical Association found solid evidence that marijuana is effective at treating chronic pain. The researchers noted “30% or greater improvement in pain with cannabinoid compared with placebo.”

Marijuana is safe when used to treat pain

A Canadian study published last year in the journal Pain found no evidence of serious side effects among medical marijuana users after a year of treatment. Users did report some incidence of “non-serious” side effects, such as coughing and dizziness, however.

Medical marijuana users are less likely to drink or take other painkillers

Research published last year in the journal Drug and Alcohol Review found that 80 percent of medical marijuana users reported substituting pot for painkillers, and 52 percent said they drank less when taking medical marijuana.

“The high rate of substitution for prescribed substances, particularly among patients with pain-related conditions, suggests that further research into cannabis/cannabinoids as a potentially safer substitute for or adjunct to opiates is justified,” the researchers concluded.

States with medical marijuana laws have fewer painkiller overdose deaths

In 2014, a study published in JAMA Internal Medicine found that states with medical marijuana laws saw a 24.8 percent reduction in opioid overdose deaths, compared with states without such laws. That worked out to about 1,700 fewer deaths in 2010 alone.

Medical marijuana availability decreases the rate of opioid dependency and death 

An NBER working paper published last year found that the presence of marijuana dispensaries was associated with a 15 percent to 35 percent decrease in substance abuse admissions and a similar drop in opiate overdose deaths.

“Our findings suggest that providing broader access to medical marijuana may have the potential benefit of reducing abuse of highly addictive painkillers,” the researchers concluded.

One important thing to note: All of the studies above were published in the past 18 months or so. This is a fairly new angle of inquiry, and the results suggest it is a highly promising one.

The CDC could play a leading role in fostering more of this type of research in the future, and the need for it is critical: Nearly 20,000 people died from prescription opiate overdoses in 2014, according to the CDC.

More from Wonkblog:

This Super Bowl ad proved just how much America loves its opioid painkillers

Why hardly anyone dies from a drug overdose in Portugal

The dramatic shift in heroin use in the past 50 years: Whiter, more suburban