"We found evidence that combined extracts of THC and CBD [cannabidiol] may reduce symptoms of spasticity in patients with MS. Although the subjective experience of symptom reduction was generally found to be significant, objective measures of spasticity failed to provide significant changes. In a previous study of spasticity-related pain, MS patients also reported a subjective perception of symptom reduction with cannabinoids [10]. However, since at least one past animal study has provided objective, physiological evidence for the antispastic properties of cannabinoids [7], the distinction between perceived symptom relief and objective physiological changes in humans should therefore be primary in future research efforts.

"Given that adverse events occurred in each reviewed trial, we also encourage future comparison studies of cannabis treatments at a wide range of dosage in order to balance potential side effects with maximum therapeutic benefit.

"Finally, there is evidence that cannabinoids may provide neuroprotective and anti-inflammatory benefits in MS. Neuroinflammation, found in autoimmune diseases such as MS, has been shown to be reduced by cannabinoids through the regulation of cytokine levels in microglial cells [25]. The therapeutic potential of cannabinoids in MS is therefore comprehensive and should be given considerable attention."

Source

Lakhan, Shaheen E and Rowland, Marie, "Whole plant cannabis extracts in the treatment of spasticity in multiple sclerosis: a systematic review," BMC Neurology (Los Angeles, CA: Global Neuroscience Initiative Foundation, December 2009) Vol. 9, p. 63.
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