For years, multiple sclerosis patients have told doctors that smoking marijuana makes them feel better. Now there is research to back up those assertions.
The study, published this week in the Canadian Medical Association Journal, found that cannabis eased pain by 50 per cent and reduced spasticity, or muscle stiffness, by 30 per cent.
"We were very, very skeptical in the beginning," said the lead researcher Jody Corey-Bloom, a neurologist at the University of California, San Diego. "But we were able to look at this objectively and, in fact, we did demonstrate some efficacy. It does at least give credence to what some patients have been saying."
The study team recruited 30 MS patients with an average age of 50.
The volunteers were divided into two groups. One group was given pot to smoke once daily for three consecutive days. Those in the other group received a placebo – it looked and smelled like marijuana, but lack the high-inducing ingredient tetrahydrocannabinol or THC. Before smoking up each day, the volunteers underwent a series of tests to evaluate pain levels, muscle spasticity and cognitive functions. Then 45 minutes after inhaling, they repeated the same tests.
After an 11-day break, they returned for three more days of tests. But this time, the groups were switched. Those who originally got the real dope were given the placebo and vice versa.
An evaluation of those results revealed a significant reduction in symptoms with cannabis. Spasticity, or muscle tightness and rigidity, is quite common in the thighs, calves and upper arms of people with MS. "It's like having a charley horse all the time," she explained. "Patients said smoking cannabis really makes a difference."
But the benefits of pot "perhaps came at a price," noted Dr. Corey-Bloom.
Cognitive tests showed a modest drop in attention, concentration and working memory while under the influence of marijuana. Patients also experienced more fatigue. The cognitive scores bounced back when the patients were retested the following morning. "We can't tell from this study whether these effects are long-lasting," she said.
Additional research may also settle another intriguing question: Can lower doses of pot produce the same or similar gains, but with significantly fewer effects on cognitive functions?