Patients who use medical marijuana for pain and other chronic symptoms can take an unwanted hit: Insurers don’t cover the treatment, which costs as much as $1,000 a month.

Once the drug of choice for hippies and rebellious teens, marijuana in recent years has gained more mainstream acceptance for its ability to boost appetite, dull pain and reduce seizures in everyone from epilepsy to cancer patients.

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Still, insurers are reluctant to cover it, in part because of conflicting laws. While 21 U.S. states have passed laws approving it for medical use, the drug still is illegal federally and in most states.

But perhaps the biggest hurdle for insurers is the U.S. Food and Drug Administration hasn’t approved it.

Major insurers generally don’t cover treatments that are not approved by the FDA, and that approval depends on big clinical studies that measure safety, effectiveness and side effects.

That research can take years and millions of dollars. And while the FDA has approved treatments like Marinol that contain a synthetic version of an ingredient in marijuana, so far, no one has gained approval for a treatment that uses the whole plant.

As a result of the obstacles, advocates for medicinal marijuana say insurers likely won’t cover the drug in the next few years. In the meantime, medical marijuana users – of which advocates estimate there are more than 1 million nationwide – have to find other ways to pay for their treatment.

Bill Britt, for instance, gets his supply for free from a friend whom he helps to grow the plants.

Britt lives mostly on Social Security income and uses marijuana every day for epileptic seizures and leg pain from a childhood case of polio.

“I’m just lucky I have somebody who is helping me out, but that could go away at any time,” said Britt, 55, who lives in Long Beach, California.

“I am always worried about that,” he said.

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