In recent years, a number of cannabis-based medicinal products have been investigated for their potential in treating symptoms associated with Multiple Sclerosis (MS). Multiple sclerosis is a chronic condition of the nervous system affecting no two patients the same. Common features include visual disturbances, muscle weakness, spasticity, pain, spasms, and altered sensation. Cannabis-based medicinal products have been evaluated in MS for the treatment of pain and spasticity.
The disease is most often diagnosed in people in their 20s and 30s and typically starts in one of two ways: with individual relapses (attacks or exacerbations) or with gradual progression. It is still not completely understood what causes MS, but it is believed that both genetic and environmental factors are involved.
The 2019 National Institute for Health and Care Excellence (NICE) review of cannabis-based medicinal products evaluated their utility for spasticity only. This review determined that in those who failed first-line medical therapies a 1:1 THC:CBD spray, Sativex®, could be offered on a 4-week trial basis if initially funded by a pay-for-response scheme. If patients see at least a 20% reduction in spasticity-related symptoms following a 4-week trial of the spray, they would then continue to have their treatment funded. However, access to the medication must be approved and supervised by a specialist clinician, and prescriptions remain low.
With such low prescription rates, high-quality evidence for the use of cannabinoids in the treatment of MS symptoms can be hard to gather. However, a review published in Current Neurology and Neuroscience Reports assessed the current evidence of the use of cannabis-based medicinal products and synthetic analogues in treating symptoms of MS.
Medical Cannabis and Multiple Sclerosis
In recent years, cannabis and its derivatives have been implicated as a potential treatment option for some symptoms of the disease. According to the MS Society (UK): “One in five people with MS we surveyed in 2014 told us they’d used cannabis to help with their symptoms.” Respondents to this survey claimed that medical cannabis had helped with muscle spasms, spasticity, and pain.
What is the Evidence?
To assess the current evidence of the efficacy of medical cannabis in this area, the researchers reviewed a total of 11 previous reviews. Of these reviews, two Cochrane reviews were identified that focused on ataxia and tremor, and spasticity. The remaining nine systematic reviews focused on Multiple Sclerosis, movement disorders more broadly, or included studies of Multiple Sclerosis as part of more comprehensive reviews of the therapeutic uses of cannabinoids.
The review concludes that there is evidence that medical cannabis and cannabinoids could be beneficial in the treatment of spasticity and pain. However, the evidence was widely inconclusive for the other common MS symptoms, such as bladder control, ataxia, and tremor. Some reviews identified a suggestion of adverse effects on disease progression, however, these studies were only conducted up to 12 weeks and therefore require further review with long-term follow up.
Although the findings were largely promising for the use of cannabinoids in the treatment of MS symptoms, the researchers conclude that more research should be conducted, as many studies focused only on short-term outcomes. It is suggested, in line with current UK recommendations, that cannabis-based medicinal products be considered for the treatment of pain and spasticity once first-line therapies have been trialed and fail to provide satisfactory relief.