Six double-blind RCTs were included in the review (n=820 patients). The sample size ranged from 14 to 395 patients. Three RCTs had a quality score of 5 points.
Five RCTs reported that cannabis extracts may decrease spasticity and improve mobility in patients with multiple sclerosis, but one RCT showed no reduction in spasticity.
One RCT showed that cannabis extracts were associated with a significant improvement in muscle tone as assessed by Ashworth scale compared with placebo (p=0.002). Five RCTs reported little to no improvement in the Ashworth scale compared with placebo.
Two RCTs reported that cannabis extracts were associated with a significant improvement in severity of spasticity as assessed by Visual Analogue Scale compared with placebo (p<0.05 and p=0.001), but one RCT reported no significant difference between the two groups.
All six RCTs reported that side effects from combined extracts of delta9-tetrahydrocannabinol and cannabidiol were generally well-tolerated.
Results of the outcomes of walking time and disability relating to mobility were also reported.