http://www.scientificamerican.com/blog/pos...mult-2009-12-02

'Doses of cannabis might help multiple sclerosis (MS) patients subdue their body spasms and move about more easily, according to a new review of recent studies. However, the authors of the paper note, the patients' apparent relief could also be a matter of perception.

After reviewing six trials that tested the effects of tetrahydrocannabinol (THC) and cannabidiol (CBD) extracts on muscle spasms in a total of 481 MS patients, the authors found "evidence that combined THC and CBD extracts may provide therapeutic benefit."

In five of the six double-blind, randomized, placebo-controlled trials the researchers analyzed, cannabis-taking patients reported decreases in their spasms. "The subjective experience of symptom reduction was generally found to be significant," wrote the authors, based at the Global Neuroscience Initiative Foundation in Los Angeles. However, the authors conceded, "participants of both active and placebo trials may not be entirely blind to their treatment status, and this may affect subjective analysis."

So despite the promising patient reports, MS patients might not get a green light for this treatment just yet. "Objective measures of spasticity failed to provide significant changes," the authors concluded in the paper, published online Wednesday in the journal BMC Neurology.

Cannabinoids have, however, been shown to offer neuro-protective benefits for MS patients by quelling inflammation through regulation of microglial cells' cytokine levels, and animal studies have revealed antispastic effects of the chemicals.' [...]