BURLINGTON (AP) -- Statistics show that medical marijuana is booming in Vermont with jumps in both patient approvals and authorized patient assistants, but production costs are high and some types of marijuana aren’t available in state.

The Burlington Free Press reported that the number of patients approved to use medical marijuana is up 90 percent from this time a year ago. That puts the total number of approved patients at more than 1,000.

Data also shows that the number of caregivers authorized to assist patients either by growing small amounts of marijuana or obtaining it from one of Vermont’s four dispensaries is up 74 percent. As of last week, there are 153 caregivers in the state.

Diane Nazarenko, 61, of North Ferrisburgh called medical marijuana "an amazing blessing." Nazarenko endured pain for years due to a back injury.

"I’m able to sleep through the night for the first time in a very long time," Nazarenko said.

But problems have arisen in the burgeoning business of growing legalized medical marijuana, said Shayne Lynn of the Champlain Valley Dispensary. Sales don’t cover the production costs, Lynn said.

Also federal laws limit certain kinds of medical marijuana, and some patients said can’t get the strains of marijuana they want in Vermont.

Despite those hiccups, analyst Matt Simon of the national Marijuana Policy Project praised the state’s efforts.

"Vermont’s law is a tremendous model of success," Simon said. "They’ve done a terrific job."

Under Vermont law, residents can receive medical marijuana if they have a debilitating medical condition. Medical marijuana was legalized in 2004.