Marijuana extract may help MS patients

Marijuana plants are seen in Chicago where officers say they discovered two football fields worth of pot plants growing on the city's South Side, Oct. 3, 2012. AP Photo/Teresa Crawford

An extract made from an active ingredient in marijuana may be able to help multiple sclerosis (MS) patients with their muscle stiffness.

MS is a chronic disease of the central nervous system, which includes the brain, optic nerves and spinal cord according to the National Multiple Sclerosis Society. About 400,000 Americans and 2.1 million people worldwide have MS, with 200 more being diagnosed every week in the U.S. Most people are diagnosed between the ages of 20 to 50, and twice as many men have MS than women. While it can develop in all ethnic groups, it is often found in Caucasians of northern European ancestry.

Symptoms occur when an immune-system attack targets myelin, the material that protects the nerve fibers of the central nervous system. It destroys the myelin and creates scarred or "sclerotic" tissue.

The disease can cause blurred vision, loss of balance, poor coordination, slurred speech, tremors, numbness, extreme fatigue, problems with memory and concentration, paralysis and blindness, among other symptoms. Muscle stiffness also occurs in 90 percent of the cases, according to the study researchers.

Researchers gave 279 patients at 22 MS treatment centers around the U.K. either a tablet that contained tetrahydrocannabinol -- an active chemical in marijuana -- or a placebo. The doses were increased gradually for the first two weeks, starting with 5 milligrams and continuing all the way to 25 milligrams. Then they were instructed to take self-assessed maintenance doses for the last 10 weeks.

By the end of the experiment, one out of four patients in the cannabis group were taking the maximum 25 milligrams as a maintenance dose. In comparison, sixty-nine percent of the placebo group was the maximum dose.

After the testing period, 30 percent of the marijuana patients reported less muscle stiffness, compared to only 16 percent taking the placebo. For patients not using antispasmodic treatment, 40 percent of the cannabis subjects reported a relief in their muscle symptoms. Throughout the study, subjects on the marijuana extract reported less pain, muscle spasms and better sleep quality than the placebo group.

However, the patients did report "known side effects" of marijuana use, such as dizziness, sleepiness, nausea and problems with attention and balance. About 93 percent reported side effects, compared to only 75 percent in the placebo group. Side effects were most observed during the first two weeks of the study.

The study was published on Oct. 8 in the Journal of Neurology, Neurosurgery, and Psychiatry.

This isn't the first study to show the benefits of cannabis for MS patients. Researched released in May in the Canadian Medical Association Journal showed that smoked marijuana was better at treating treatment-resistant spasticity or excessive muscle contractions than the placebo.

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