An oral oil containing tetrahydrocannabinol (THC) and cannabidiol (CBD) led to a significant and meaningful reduction in motor and vocal tics in patients with severe Tourette syndrome (TS), according to the results of a double-blind, placebo-controlled, crossover study published in NEJM Evidence.
The study included 22 adults with severe TS who received THC:CBD oil titrated upward over 6 weeks to a daily dose of 20 mg of THC and 20 mg of CBD, followed by a 6-week course of placebo. Of the participants, only six had not previously used cannabis.
The primary outcome measure was the total tic score on the Yale Global Tic Severity Scale (YGTSS), with higher scores indicating greater tic severity. The researchers found that after 6 weeks, the reduction in the total tic score was significantly higher with THC:CBD (8.9) compared to placebo (2.5).
In addition to reducing tics, THC:CBD also led to a decrease in symptoms of obsessive-compulsive disorder (OCD) and anxiety, which often coexist with TS.
A Viable Treatment Option
These findings provide strong evidence for the effectiveness of THC:CBD oil in suppressing tics and improving comorbid symptoms in severe TS. The study was conducted independent of any drug company sponsorship, adding to its methodological robustness.
Neuropsychiatrist and lead investigator Philip Mosley, PhD, commented, “We need a plurality of treatment options in Tourette syndrome. For some, antipsychotics are effective tic-suppressing agents, but for many, these benefits are complicated by side effects such as weight gain and sedation.” He also highlighted the biological plausibility of cannabinoids as therapeutic agents, given the high concentration of the body’s own endocannabinoid receptors in the basal ganglia, which is the neuroanatomical nexus of TS.
Based on the findings of this small trial, larger and longer trials of THC:CBD in TS are warranted. The positive results of this study support the use of medicinal cannabis as a potential treatment option for patients with TS.
The study provides compelling evidence for the efficacy of THC:CBD oil in reducing tics and alleviating comorbid symptoms in severe Tourette syndrome. This oral oil offers a potential alternative for patients who have not found relief with other medications or who have experienced intolerable side effects.
While further research is needed to fully understand the long-term effects and safety of THC:CBD in TS, these findings open new avenues for the medical community to explore novel treatments for this challenging condition.