Chronic pain patients who use medical marijuana had no difference in serious side effects than patients who were not using cannabis for pain control. Dr. Ware and Canadian colleagues report in the Journal of Pain the results of their chronic pain study. The long term effects of marijuana were studied in a chronic pain (including chronic back pain) population and compared with those who didn’t take cannabis medication. Dr. Ware’s study found no difference in what they consider serious side effects of the kidney damage, liver damage. However, the patients experienced minor side effects of headaches and Nausea. According to this observational study patients do not sustain major organ damage as a result of medical marijuana use. In the same vein one can assume that patients who use marijuana for other medical conditions would be equally safe.