June 9, 2004
Multiple Sclerosis Society
Pain affects approximately half of all people with MS and is also a common symptom in other conditions. A significant amount is as a direct result of MS damaging nerves, known as neuropathic pain. Unfortunately, this type of pain responds poorly to standard drugs and this often long-term symptom, is difficult to treat effectively. There are anecdotal reports that cannabis is beneficial for a range of symptoms associated with MS, including pain, nausea and sleep problems, although research-based evidence to support this view is limited.
This study looked at the effectiveness and safety of two cannabis extracts, called tetrahydrocannabinol (THC) and cannabidiol (CBD), alone and in combination, in people with long-term pain. All results were compared to a placebo (a “control” substance known to cause no effect).
32 participants with long-term pain (as a result of different conditions, including MS) took part in the study. The most effective cannabis dose was determined in an initial phase of the study and each participant received THC alone, CBD alone, THC and CBD in combination and placebo for two separate one-week periods over the eight-week study period. All treatments were administered via a spray under the tongue. Each participant self-rated the severity of their two worst symptoms, their sleep and any side effects, before administration of any treatments and on a daily basis for the duration of the study.
Results showed that both the combination treatment and THC alone significantly improved the two main pain-related symptoms nominated by the participants. CBD alone was not found to have any effect. All cannabis extracts were found to significantly increase the number of “good” nights of sleep, although not lengthen the number of hours of sleep. The main side effects were dry mouth, drowsiness and feelings of euphoria (feeling “high”).
In summary, both THC alone and in combination with CBD were effective in relieving pain and improving sleep in this small group of participants. The authors suggest that the next steps are to study cannabis extracts in a wider selection of specific pain problems in order to determine the full extent of potential benefits.
This report was published in Anaesthesia, 2004. Vol. 59, pages 440-452.
Copyright © 2004, Multiple Sclerosis Society