(HealthDay News) – Smoking cannabis is associated with a reduction in spasticity for patients with multiple sclerosis (MS), according to a study published online May 14 in CMAJ, the journal of the Canadian Medical Association.

Jody Corey-Bloom, MD, PhD, from the University of California San Diego in La Jolla, and colleagues conducted a placebo-controlled crossover trial to investigate the short-term effect of smoked cannabis on spasticity in MS. Thirty-seven adult patients with MS and spasticity were randomly allocated to smoke cannabis or identical placebo cigarettes once daily for three days. Participants crossed over after a washout period of 11 days. The change in spasticity, as measured by patient score on the modified Ashworth scale, was the primary outcome. Patient perception of pain, a timed walk, and changes in cognitive function were secondary outcomes. Thirty patients completed the study.

The researchers found that smoked cannabis was associated with significantly reduced spasticity, with an average reduction of 2.74 points more than placebo in the modified Ashworth scale scores. Treatment also significantly reduced pain by an average of 5.28 points more than placebo on a visual analog scale. There was no significant difference for a timed walk between the groups. Smoked cannabis treatment resulted in a significant reduction in cognitive function, with a decrease of 8.67 points more than placebo on the Paced Auditory Serial Addition Test. There were no serious adverse events noted during the study.

“Using an objective measure, we saw a beneficial effect of inhaled cannabis on spasticity among patients receiving insufficient relief from traditional treatments,” the authors write. “Although generally well tolerated, smoking cannabis had acute cognitive effects.”

Full Text