Cannabis may be an effective treatment for Tourette syndrome, a new study suggests.

Researchers from the University of Toronto found that in 18 of the 19 study participants who used cannabis routinely for at least two years, Tourette’s symptoms were “much improved.”

“Several of my patients with Tourette syndrome had noticed that if they used some marijuana, their tics decreased significantly,” said Elia Abi-Jaoude, one of the study’s corresponding authors, in a PsyPost report.

“We began prescribing medical cannabis at our clinic and were struck by the improvements we saw in tics and related symptoms. We eventually decided that we should investigate this topic further.”

Abi-Jaoude added that the study – published in the Journal of Neuropsychiatry and Clinical Neurosciences – did have some setbacks, including its relatively small sample size and its lack of placebo control. There were also several different cannabis strains used in the study, meaning researchers couldn’t make “reliable conclusions about which cannabis strains or ingredients are most helpful for tics and related symptoms.”

“This was a retrospective study, so there may be a ‘recall bias’ when people try to compare how they are doing now to how they were doing before starting cannabis,” he said.

The next step, said Abi-Jaoude, is a controlled double-blind study featuring different cannabis strains. That said, he is confident that cannabis is a “promising treatment for tics and related symptoms.”

“We hope that with further research we can get a clearer picture of the potential benefits and risks with using cannabis for tics and related symptoms,” he said.

h/t Ganjapreneur, PsyPost