Review paper examines cannabis as a treatment for multiple sclerosis

The authors of this review are representatives of the Saint James School of Medicine in Illinois and the School of Natural Sciences at Kean University in New Jersey. Their review, “Neurological Benefits, Clinical Challenges, and Neuropathologic Promise of Medical Marijuana: A Systematic Review of Cannabinoid Effects in Multiple Sclerosis and Experimental Models of Demyelination,” was published Feb. 24 in the journal Biomedicines and analyzes 28 different studies related to multiples Sclerosis. These final studies were selected from a pool of 119 articles that could be included in this review.

Symptoms of multiple sclerosis often include fatigue, restricted movement, speech disorders, chronic neuropathic pain, anxiety, depression, and a host of other effects. In their review, the researchers note that patients are dissatisfied with currently available treatments for their condition, motivating the researchers to “look for complementary remedies in hopes of preventing breakthrough relapses and worsening disability.”

Fourteen of the 28 studies involved the use of animal models in researching the effects of cannabis. Overall, the study authors concluded that “the combined experimental results adequately demonstrate that cannabinoid treatments are effective” and reduce a variety of symptoms. The authors noted that the studies were promising but cannot replace testing in humans. “While the internal validity in the preclinical studies was very good because the experiments were well designed and well controlled, the external validity of animal studies is less certain due to differences in cannabinoid systems between species affecting safety, dose response, tolerability and may affect homeostasis.”

Researchers also evaluated 14 human studies using Sativex®, a cannabis-based oral spray approved for multiple sclerosis in the EU, UK and Canada, but not yet in the US. “The growing body of medium-quality evidence supporting the safety and efficacy of cannabinoid treatment with 1:1 THC/CBD blends has led to its approval in some countries for the treatment of spasticity, pain and bladder dysfunction in MS,” the authors wrote . “Our assessments are consistent with those of others, finding that the magnitude of the impact on short-term neurological outcomes in MS patients is either small, limited, or moderate, and that the benefits are identifiable through subjective rather than objective measures.”

Nine of the studies analyzed the effectiveness of cannabis on muscle spasms, five assessed cannabis and pain, three examined lower urinary tract function, and three examined sleep quality.

The authors of this review conclude that, similar to most other research initiatives involving cannabis, while there is promising evidence that cannabis can help treat multiple sclerosis and a variety of symptoms, more studies are needed. “Future studies are recommended to investigate the cellular and molecular mechanisms of the effects of cannabinoids on MS lesions and to evaluate whether medical marijuana can accelerate remyelination and delay disability development in the long term.”

The National MS Society states that 2.3 million people have multiple sclerosis worldwide and that over one million people have multiple sclerosis in the United States. The organization’s stance on medicinal cannabis is supportive and also calls for more research to support the evidence for cannabis as a treatment for multiple sclerosis. “The [National MS] The Society supports the right of people with MS to work with their healthcare provider to access cannabis for medicinal purposes, as permitted by law in states where such use has been authorized. In addition, the Society supports the need for more research to better understand the benefits and potential risks of cannabis and its derivatives as a treatment for MS and its symptoms.”