Medical marijuana poses challenges for the workers compensation industry, but some experts and recent research say it could be an alterative to long-term opioid use.

There’s a growing consensus among workers comp payers and doctors that “any treatment that could reduce opioid dependency is something to look into, or something to keep an eye on,” said Tom Atchison, associate attorney at Heacox, Hartman, Koshmrl, Cosgriff & Johnson P.A. in St. Paul, Minnesota.

Long-term opioid use can be unsafe for injured workers and costly for payers, Mr. Atchison said.

On Monday, the Minnesota Department of Labor and Industry adopted a rule establishing criteria for long-term opioid treatment that also said medical marijuana is not an “illegal substance” for injured workers under state law.

It remains illegal under federal law, however.

The U.S. Food and Drug Administration has not approved marijuana for any medical condition, so it’s difficult to compare its effects with other drugs used in workers comp, such as opioids, said Dr. Damon Raskin, a Pacific Palisades, California, internist who specializes in treating addiction and substance abuse. However, “the risk of death and other severe addiction issues with opiates make looking at (medical marijuana) more palatable,” he said.

“Until I see good scientific evidence that this is something that works (for pain), it’s going to be hard to endorse,” Dr. Raskin said. “But if there’s a choice…