(Photo by Stina Sieg-KJZZ)

Medical marijuana sales exploded in Arizona last year. Dozens of new dispensaries opened, like the Giving Tree in North Phoenix.

A University of Arizona researcher has received permission from the Obama Administration to test medical marijuana on patients with Post Traumatic Stress Disorder, but the state state still has final say on whether PTSD patients can use it here.

Suzanne Sisley has been waiting three years for federal approval to start her research involving veterans. Opponents contend she is only trying to expand medical marijuana programs, but Sisley said her research is objective.

“If this study produces data that show marijuana is a deeply dangerous drug...that its damaging to vets, that it exacerbates psychiatric symptoms…then all of that data will be published," Sisley said.

She added her study still needs final approval from the Drug Enforcement Administration to transport pot to Arizona from Mississippi. Earlier this year, Arizona decided not to allow patients with PTSD to qualify for medical marijuana.   

The Department of Health Services’ director said more research needs to be done.