The Oregon Psilocybin Therapy Initiative and campaign for Initiative Petition #34 said it gathered 164,782 signatures, according to its website.
"Oregonians now have a legitimate shot to give true access to licensed psilocybin therapy," the campaign said in a statement.
The signatures will have to be verified before it qualifies for the ballot.
The campaign said they should know if its approved by mid-July, The Oregonian reported. if approved by voters, the measure would legalize psychedelic mushrooms in controlled doses and would only be administered by professionals.
It would make Oregon the first state to legalize the substance, according to the newspaper. Oakland, Calif., and Denver have already decriminalized psilocybin.
“Pioneering research at institutions like Johns Hopkins, NYU, and UCLA has shown the significant promise of psilocybin therapy,” the campaign said in a press release.
Under the measure, people would not be allowed to grow psychedelic mushrooms and only license-holders would be able to provide psilocybin therapy.
“Oregon has some of the highest rates of depression, anxiety, and addiction in the country,” Sheri Eckert, a chief petitioner, said in the release, according to the newspaper. “As a therapist, I am intimately aware of how mental health affects our communities -- not only people suffering from mental health conditions but their families and loved ones as well."