TUESDAY, Oct. 9, 2012 (HealthDay News) -- A marijuana extract appears to ease painful muscle stiffness in people with multiple sclerosis, according to a new British study.
Muscle stiffness -- which affects up to 90 percent of multiple sclerosis (MS) patients during the course of their disease -- reduces mobility, interferes with daily routines and affects sleep. Current treatments often fail to fully relieve symptoms and many MS patients try alternative therapies, including marijuana.
In the new study, which included nearly 300 adults with MS from 22 treatment centers in the United Kingdom, patients with stable disease were randomly selected to receive either an extract of the active chemical in marijuana (tetrahydrocannabinol) or an inactive placebo each day for 12 weeks.
The treatments were given in gradually increasing daily doses, from 5 milligrams up to a maximum of 25 mg for two weeks, followed by maintenance doses for the remaining 10 weeks, according to the report published in the Oct. 8 issue of the Journal of Neurology, Neurosurgery and Psychiatry.
After 12 weeks, muscle stiffness was eased in about 30 percent of the patients taking the marijuana extract and just less than 16 percent of those taking the placebo, the researchers reported.
The difference in relief of muscle stiffness was evident after four and eight weeks, and also included improvements in pain, muscle spasms and sleep quality at all points in the study.
The findings suggest that the marijuana extract could be a useful treatment for muscle problems in MS patients and could provide effective pain relief, especially for those in considerable pain, researcher John Peter Zajicek, of the University of Plymouth in the United Kingdom, and colleagues, pointed out in a journal news release.
Side effects noted in those treated with the marijuana extract were "consistent with the known side effects" of marijuana use, including dizziness, problems with attention and balance, sleepiness, dry mouth, nausea, diarrhea, fatigue and confusion, the researchers pointed out in the report.
"No new safety concerns were observed," however, the study authors added.
The U.S. National Institute of Neurological Disorders and Stroke has more about multiple sclerosis.