Smoking Cannabis Relieves Pain For Multiple Sclerosis Patients
May 15, 2012

Smoking Cannabis Relieves Pain For Multiple Sclerosis Patients

Connie K. Ho for

The benefits and drawbacks of cannabis have long been discussed in the medical community. And now, a new study looks at how cannabis can affect the pain of multiple sclerosis (MS) patients.

Many patients of MS report to have spasticity, which is a condition that makes their muscles tight and difficult to control. There are some drugs that are available, but many of these treatments tend to not show improvement in patients´ conditions. The report, recently published in the Canadian Medical Association Journal, states that smoking cannabis could help reduce muscle tightness and pain for MS patients. However, smoking cannabis could also have negative cognitive effects.

In the experiment, researchers from the University of California, San Diego (UCSD), held randomized, double-blinded controlled trials with 30 participants. They hoped to better understand if smoking cannabis could affect muscle spasticity for patients who weren´t able to respond to other treatments. Scientists rated the spasticity of patients´ joints on the Ashworth scale, which has commonly been used to look at the intensity of muscle tone. The results of the project showed that pain scores decreased by 50 percent and that the participants who smoked cannabis showed a one-third decrease in the Ashworth scale, which was 2.74 points on a base scale of 9.3.

Overall, spasticity in patients improved compared to a placebo group in the experiment. In the group of participants, 63 percent were female, the average age was 50, 20 percent used wheelchairs, and more than half the participants needing walking aids. This experiment differed from past projects in that it looked at the impact of smoked cannabis instead of oral cannabis.

"We saw a beneficial effect of smoked cannabis on treatment-resistant spasticity and pain associated with multiple sclerosis among our participants," noted Dr. Jody Corey-Bloom, a researcher of the Department of Neuroscience at UCSD, in a prepared statement. "Although generally well-tolerated by our participants, smoking cannabis was accompanied by acute cognitive effects."

Participants were also asked to perform an additional test with focused attention. The test showed that cognitive function was affected negatively by the group of participants who smoked cannabis. The mild effects on attention and concentration as well as increased fatigue proved to be short-term.

"Using an objective measure, we saw a beneficial effect of inhaled cannabis on spasticity among patients receiving insufficient relief from traditional treatments," stated the authors in summarizing their research. "Although generally well-tolerated, smoking cannabis had acute cognitive effects. Larger, long-term studies are needed to confirm our findings and determine whether lower doses can result in beneficial effects with less cognitive impact.”

Researchers believe that more studies need to be done to confirm their findings to see if lower doses of smoking cannabis can have positive results, but with less of a cognitive impact.

The majority of people with MS experience cognitive changes at some point in their lives," remarked Dr. Nicholas LaRocca, vice president of health care delivery at the National Multiple Sclerosis Society (NMSS) and a non-affiliate of the study, in an interview with MSNBC's Rachael Rettner. "We don´t want to add any additional cognitive deficits with treatment.”

This study was the fifth clinical test on the possible effectiveness of cannabis, as reported by the University of California Center for Medicinal Cannabis Research (CMCR - There have been four other human studies by the CMCR that examined the control of neuropathic pain, all of which have showed positive results. The CMCR helped provide funding for the current study.

"The study by Corey Bloom and her colleagues adds to a growing body of evidence that cannabis has therapeutic value for selected indications, and may be an adjunct or alternative for patients whose spasticity or pain is not optimally managed," commented Dr. Igor Grant, director of the CMCR.

According to MSNBC, researchers are also looking at possible treatments for MS patients with exercise and Botox injections.

"We need to continue to explore all of those possibilities, because any given person with MS may respond better to one [treatment] than another," LaRocca of the NMSS told MSNBC.