Medical marijuana reviewed

There's evidence that marijuana is moderately effective in treating some conditions it's often prescribed for, and not as much for others, according to a review commissioned by the Swiss Federal Office of Public Health.

Researchers combed through previous research—about 80 randomized trials involving 6,500 people, according to WebMD.com. They concluded that there's moderate evidence to support the use of marijuana to treat chronic pain, muscle spasms and involuntary movements, but found it's not as effective against nausea and vomiting due to chemotherapy, weight loss due to HIV, sleep disorders or Tourette syndrome, a condition characterized by repetitive motions or sounds.

Pro-marijuana group NORML is critical of the authors' conclusions. Deputy Director Paul Armentano said that, while only two of the studies reviewed evaluated medical marijuana itself rather than a derivative or synthetic THC, many more clinical trials using real pot have been conducted but were not included.