“We have a weird form of capitalist communism with cannabis in D.C.,” says Adam Eidinger, the co-founder of DC Marijuana Justice, a group fighting for equal rights for cannabis users and growers. All of the city’s medical marijuana comes from a few highly regulated growers in the District, he says, and when you add “a 10 percent sales tax on medicine” on top of that, the result is extraordinarily expensive weed.

A new study by Oxford Treatment Center, a Mississippi facility associated with American Addiction Centers, found that D.C. is the jurisdiction with the highest weed prices in the nation, and the competition isn’t even close. The report, sourced from a user-submitted global price index of marijuana, found that the average price for an ounce of high-quality marijuana in the District is $597.88, nearly twice the national average of $326.06. In North Dakota, the second-most expensive place to get high in the U.S., the average price of high-quality kush drops to $383.60 an ounce, and in Oregon, it costs a mere $210.75. With legal weed and a lot of farmland, Oregon has experienced a recent boom in marijuana production. Some West Coast dispensaries sell ounces for as little as 40 bucks.

This isn’t just a problem for Saturday night stoners. The high prices create a major barrier to treatment for people who rely on marijuana for pain management, a problem that has been amplified now that the opioid crisis has made prescription painkillers harder to obtain.

Sondra Battle has fibromyalgia, an intensely painful neurological disease that, when it’s bad, prevents her from standing. She formerly used a prescription opioid called Tramadol to treat it, but “because of the opioid guidelines I can’t get it anymore,” she says. “The only options my doctor offered were Motrin and Tylenol, but for my pain, that’s like having a Tic Tac.”

Getting cut off from prescription opioids made medical marijuana more critical to Battle’s healthcare than ever, but since weed’s so expensive and isn’t covered by insurance, she can’t afford to obtain enough to properly manage her pain. “I’m disabled. I receive SSI [Supplemental Security Income, which provides assistance to people with disabilities]. That’s my only source of income right now,” she says. “I can’t afford to stay medicated through the month.” Since having enough marijuana to treat her pain every day is impossible, she emphasizes, “I have days where I just suffer through.”

Battle was a fierce advocate in the fight for medical marijuana in D.C., which makes the fact that the current system is so cost-prohibitive even more exasperating. “After advocating so hard, it feels terrible that it’s not really helping me. It would be beneficial for me if I could grow,” which would make it affordable for her to use her own stash, she says, “but I’m in public housing right now,” where home-growing is banned.

“The program isn’t set up to benefit patients,” she argues. “If it was truly for patients, the prices would be like California. I looked at California’s dispensaries—it’s like a third of the price as in D.C. And they have delivery, which D.C. doesn’t have.”

Michael Bobo, one of the owners of National Holistic Healing Center, a medical dispensary in Dupont, says that in his view, the prices have been dropping in D.C. as more growers have popped up. That, along with the opioid crisis, has had a very clear effect on the amount of people accessing care. “If you’re looking at healthcare options and it’s too expensive for you to be able to maintain, you’re going to look elsewhere.” But if it’s affordable, he says, “the opioid crisis has people seeking medical cannabis as a first option rather than a last option.”

Bobo’s dispensary is one of only six in D.C., and they all have to source their weed from just eight different warehouses growing marijuana in the District. Each cultivator is limited to 1,000 plants. Battle says that the limited supply—both the number of places that sell weed and the number that grow it—keeps prices so high.

“Why do we have any restrictions on the numbers of points of sale?” asks Eidinger. When the District was first setting up its medical marijuana program, he says, “we told them that this is going to result in high prices and low participation for the program.” (According to the Department of Health, there are about 5,900 patients registered in the program.)

He claims that if the city only allows weed to be grown in warehouses in the District, prices inevitably are going to be high. “We don’t have any farmland in D.C.!” he points out. “This is industrial agriculture indoors. It’s very, very expensive … There are huge electrical bills. We’re wasting what little warehouse space we have on a plant that should be grown outdoors.” If the District is going to drive down prices, he argues, it needs interstate commerce (i.e. legal weed coming from other states with more agriculture) and to grant permission for home-growers to sell their product, an act that is currently banned.

Eidinger doesn’t think the District is taking the issues with marijuana prices seriously. “The only point of this whole thing is to make money for the city,” he says. “They don’t care about patients.”