“Cannabis-based medications have been demonstrated to relieve pain.
Cannabis medications can be used in patients whose symptoms are not adequately alleviated by conventional treatment.
The clinical effect of the various cannabis-based medications rests primarily on activation of endogenous cannabinoid receptors.
Consumption of therapeutic amounts by adults does not lead to irreversible cognitive impairment.”
http://www.sciencedaily.com/releases/2012/08/120807101232.htm