Maine state health officials said they need to see more science before adding "opiate abuse disorder" to the list of qualifying conditions for medical marijuana.
"We have no proof to say that it would work," said State Health Officer Dr. Christopher Pezzullo, who collaborated with DHHS officials to decide against a petition to make opiate abuse a qualifying condition.
Marijuana advocates have argued that medical cannabis helps patients suffering with chronic pain find an alternative to addictive painkillers, that can lead to heroin abuse.
"We're seeing this on a day-to-day basis," said Brad Feuer, CEO of Integr8 Health.
Feuer said caregivers are regularly working with patients to manage chronic pain with cannabis, and have even seen patients who used it to quit heroin.
"Patients are overjoyed when they come in and say, 'I'm not using narcotics anymore,'" said Dr. Herman Lerner, at Integr8 Health in Falmouth, Maine.
Lerner said he is frustrated the state denied the petition, arguing it could have made an impact in the fight against opiate abuse.
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"I think we have the best possible approach," he said.
In a survey of more than 500 of its patients, Integr8 Health said 39 percent of patients report using cannabis to completely stop opioid use.
While DHHS acknowledges that anecdotally, some patients may see success, officials say the results are mixed.
"There's some research in animals that suggests it might be helpful, however there are also several of those animal studies that suggest it might be harmful," said Dr. Pezzullo.
He said additionally, there have been no completed human studies.
"You can't really take the report of one person -- you really need to have a study to make sure it will be safe for all," he said.
Meanwhile, those working on the campaign to legalize recreational marijuana in Maine are using this as one more argument for voting "Yes on 1" this November.
"It definitely gives us more urgency, when we're in this middle of this opioid crisis," said David Boyer, Maine State Director for the Campaign to Regulate Marijuana Like Alcohol.
"[Cannabis] seems like it can work."