FARGO - North Dakota voters overwhelmingly approved the legalization of medical marijuana, and lawmakers are grappling with launching the program. But patients are about to learn that legalization does not mean insurance will cover the cost.

Major health insurers in North Dakota have said they will not provide coverage for medical marijuana, which voters approved in the November election by a margin of almost 64 percent, citing what they say is inadequate evidence of its effectiveness.

“We don’t cover it in Minnesota nor will we in North Dakota,” said Greg Bury, senior manager for public relations at Medica. “We don’t believe the efficacy has yet been established.”

Medica’s policy, Bury said, is to “look for evidence-based literature and studies that demonstrate safety, effectiveness and effect on health outcomes.

Thus far, he said, Medica believes that evidence is lacking to justify coverage of medical marijuana.

The positions of Blue Cross Blue Shield of North Dakota, the state’s largest private health insurer, and the Sanford Health Plan are similar - reflecting a stance taken by the industry elsewhere in states that allow medical marijuana, including Minnesota.

Because the dispensation of medical marijuana is not approved by the Food and Drug Administration, health insurers encounter significant obstacles in providing coverage, said Andrea Dineen, a spokesperson for Blue Cross Blue Shield of North Dakota.

“Like most health insurance companies across the nation, Blue Cross Blue Shield of North Dakota does not cover drugs that are not FDA approved,” she said in a statement.

To gain FDA approval, Dineen added, drugs must undergo extensive testing to prove safety and effectiveness. “This has not occurred for medical marijuana,” she said.

Similarly, the Sanford Health Plan does not cover medical marijuana, but a spokeswoman said she couldn’t elaborate on the reasons.

The lack of coverage for medical marijuana extends to many public health insurers.

A bill before the North Dakota Legislature, for example, would prohibit coverage for medical marijuana under the state’s workers’ compensation program, administered by Workforce Safety & Insurance, or WSI.

WSI’s advisory board will review the legislation and decide whether to support or oppose the bill, but the agency has some practical questions about how it would provide coverage, Clare Carlson, WSI’s deputy director said.

“A number of agencies and organizations in North Dakota have similar questions,” Carlson added. “There are many details to be addressed before we can effectively manage a program that includes marijuana.”

One of those questions, he added, is how to pay for coverage. “Currently marijuana is illegal at the federal level,” Carlson said. Also, dosages vary greatly and there is no established system to send payment and even a question as to who to pay, he said.

Ray Morgan of Fargo, a leading proponent of North Dakota’s medical marijuana program, said he is not surprised to see the state’s insurers follow other states in not covering the drug.

“Ultimately, the problem you have with this is it’s not recognized by the FDA,” he said, though predicted that will change, perhaps in a decade, as more and more states legalize medical marijuana.

Morgan said “evidence keeps mounting up” that medical marijuana can be used to treat a variety of ailments. “To think this is not going to continue is a fool’s paradise,” he said.

In Minnesota, which established its medical marijuana program in 2014, some patients and their families have been unable to afford the cost of medical marijuana provided by eight approved dispensaries around the state, including one in Moorhead, Minn.

Amber Solum of Moorhead, whose teenaged son suffers 45 to 100 epileptic seizures a day, has a prescription for medical marijuana, but her family can’t afford the drug.

“It’s astronomical,” she said in October. “It’s $800 a month,” and not covered by insurance.

So far, 5,046 patients have enrolled in Minnesota’s medical marijuana program, and 4,097 are considered active patients, according to figures from the Minnesota Department of Health, which oversees the program.

The largest percentage of patients, 42 percent, use marijuana to treat intractable pain, followed by 31 percent for muscle spasms, 18 percent for cancer, 10 percent for seizures and 5 percent for inflammatory bowel disease, including Crohn’s, the health department reported.