Several studies have demonstrated the therapeutic potential of cannabis and its derivate products to manage the symptoms of multiple sclerosis (MS) and other neurodegenerative diseases. But there is still much to be done to enhance their use and accessibility to patients who may benefit from these therapies, according to a recent presentation by Matthew Makelky, PharmD.
Makelky, a researcher at the University of Colorado, reviewed the current status and advances made in cannabinoids use for MS at the 2018 Annual Meeting of the Consortium of Multiple Sclerosis Centers (CMSC) in Nashville, Tennessee, May 30-June 2. The presentation was titled “Hashing it out: Cannabis for Multiple Sclerosis.”
The use of marijuana for medical purposes is currently legal in 29 states in the U.S. Only nine of those states also allow recreational marijuana use. With the trend toward legalizing cannabis, additional pressure lies on clinicians who prescribe it to ensure proper use and administration.
Cannabis contains more than 100 pharmacologically active compounds (cannabinoids), with the most studied compounds being the tetrahydrocannabinol (THC) and cannabidiol (CBD). Both have been evaluated for their potential to modulate spasticity associated with MS, as well as to manage seizures, inflammation, pain, anxiety, and other conditions.
Theoretically, CBD holds greater therapeutic potential than THC, since the first does not have the psychoactive properties that accompany THC use. Still, this compound is linked to some adverse side effects, such as drowsiness, decreased appetite, diarrhea, fatigue, and convulsion.
The THC compound is the one responsible for the “high” experience people feel when consuming cannabis, and is linked to increased neurological risk. THC has been associated with altered brain development and cognitive impairment when used in early adolescence, but also to an increased risk of chronic psychosis disorders.
According to the American Academy of Neurology, the use of oral cannabis extract (OCE) and synthetic THC improved spasticity-related symptoms and pain in patients with MS.
In contrast, AAN considers there is limited or insufficient evidence demonstrating the effectiveness of oromucosal cannabinoid spray, such as Sativex (nabiximols), or smoked cannabis for these indications.
As for treating MS-related urinary symptoms and tremor, none of the tested forms of cannabinoids have shown compelling evidence of effectiveness, according to Makelky.
There are some cannabinoid-based drugs already available on the market and others are under development. Because of the different effects of each cannabinoid compound, finding suitable dosages and methods of administration, as well as optimal frequency of use, may be both challenging and risky.
Also, cannabinoids may chemically react with other prescribed drugs — increasing or reducing their effects — which adds another layer of potential hazard that should be discussed between patients and clinicians.
In summary, cannabis-derived compounds hold potential to treat MS and “to help specific disease states,” Makelky said. Still, there is a lot to learn about “the complex metabolism and interaction profiles” of these compounds, he added.