Smoking cannabis daily can significantly reduce the chronic nerve pain experienced by many HIV-infected patients, according to results of a trial conducted at the University of California, San Francisco.

The study, reported in the journal Neurology, included 50 patients who had been infected with HIV for an average of 14 years and had nerve pain for an average of 7 years. On a scale of 0 (no pain) to 100 (the most pain), the subjects’ pain ratings averaged 53, despite the fact that many were taking other medications, such as narcotics to control the pain.

Twenty-five patients were assigned to smoke cannabis and 25 were assigned to inactive “placebo” cigarettes. Over a 5-day period, subjects could smoke up to three cigarettes a day and they also continued using prescribed analgesics.

Dr. Donald Abrams and colleagues report that the first cigarette reduced chronic pain over the next 95 minutes by around 72 percent in the cannabis group versus 15 percent in the placebo group.

Subjects who smoked cannabis were more likely to experience anxiety, sedation, disorientation, confusion and dizziness than were subjects given placebo. However, none of these side effects presented a serious safety concern, the researchers point out.

Cannabis “may indeed be useful in the amelioration of a very distressing, disabling, and difficult-to-treat complication of HIV,” Dr. Igor Grant, director of the University of California’s Center for Medicinal Cannabis Research, remarked in a UCSF press release.

SOURCE: Neurology, February 13, 2007.