August 6 (HealthDay News) -- Medicinal marijuana helps relieve neuropathic pain in people with HIV, says a University of California, San Diego, School of Medicine study.

It included 28 HIV patients with neuropathic pain that wasn't adequately controlled by opiates or other pain relievers. The researchers found that 46 percent of patients who smoked medicinal marijuana reported clinically meaningful pain relief, compared with 18 percent of those who smoked a placebo.

The study, published online Aug. 6 in Neuropsychopharmacology, was sponsored by the University of California Center for Medical Cannabis Research (CMCR).

"Neuropathy is a chronic and significant problem in HIV patients as there are few existing treatments that offer adequate pain management to sufferers," study leader Dr. Ronald J. Ellis, an associate professor of neurosciences, said in an UCSD news release. "We found that smoked cannabis was generally well-tolerated and effective when added to the patient's existing pain medication, resulting in increased pain relief."

The findings are consistent with and extend other recent CMCR-sponsored research supporting the short-term effectiveness of medicinal marijuana in treating neuropathic pain.

"This study adds to a growing body of evidence that indicates that cannabis is effective, in the short-term at least, in the management of neuropathic pain," Dr. Igor Grant, a professor of psychiatry and director of the CMCR, said in the UCSD news release.

SOURCE: University of California, San Diego, news release, Aug. 6, 2008