Medical Cannabis Alleviates Chronic Pain

A new study reports on the scientific value of medical cannabis for patients with human immunodeficiency virus-associated neuropathic pain.

Researchers from the University of California San Francisco (UCSF; USA) conducted a randomized, placebo-controlled clinical trial of 50 patients with painful sensory HIV-associated neuropathy between May 2003 and May 2005. The patients reported an average of six years of neuropathic pain. Patients were randomly assigned to smoke either cannabis (3.56% tetrahydrocannabinol) or identical placebo cigarettes with the cannabinoids extracted three times daily for five days. The analgesic and anti-hyperalgesic effects of smoked cannabis were assessed using a cutaneous heat stimulation procedure and the heat/capsaicin sensitization model.

The study showed that smoked cannabis reduced daily pain by 34%. A greater than 30% reduction in pain was reported by 52% in the cannabis group and by 24% in the placebo group. The first cannabis cigarette smoked reduced chronic pain by a median of 72%, compared to 15% with placebo. Cannabis reduced experimentally induced hyperalgesia to both brush and hair stimuli, but appeared to have little effect on the painfulness of noxious heat stimulation. No serious adverse events were reported. The results of the study were published in the February 2007 issue of the journal Neurology.

"Smoked cannabis was well tolerated and effectively relieved chronic neuropathic pain from HIV-associated sensory neuropathy. The findings are comparable to oral drugs used for chronic neuropathic pain,” concluded Dr. Donald Abrams, M.D., of the hematology-oncology clinic at UCSF, and colleagues.

"This study demonstrates the potential effectiveness of medical cannabis to treat the chronic pain of people living with HIV/AIDS,” said Dr. Barbara T. Roberts, director of medical and scientific affairs for Americans for Safe Access, and a former senior policy analyst at the United States White House office of national drug control policy. "In addition to people living with HIV/AIDS, there are thousands of vets returning from Iraq who will spend decades coping with neurological pain.”


Related Links:
University of California San Francisco
Americans for Safe Access