Cannabis Medicinal Extracts
Among numerous cannabinoid compounds from plants belonging to the genus Cannabis, delta-9-tetrahydrocannabinol (THC) is known to have psychoactive effects while cannabidiol (CBD) is a non-psychoactive component that may have antioxidant and anti-inflammatory properties, as well as the ability to modulate the psychoactive effects of THC (Atakan 2012; Wade et al. 2003; Nabata et al. 2020).
More information about cannabis and SCI can be found here.
The use of cannabis medicinal extracts (CME) with SCI-related fatigue has not been widely researched yet. Only one RCT has investigated the use of CME through sublingual delivery and self-titration, its effect on neurological symptoms such as fatigue, and its potential side effects (Wade et al. 2003).
Discussion
In a double-blind, randomized, placebo controlled single patient crossover trial, researchers explored the use of CME and their effect on neurological symptoms such as fatigue, spasticity, pain, and bladder incontinence in participants with MS (N = 18), SCI (N = 4), brachial plexus damage (N = 1), and limb amputation due to neurofibromatosis (N = 1) (Wade et al. 2003). This included THC, CBD, and 1:1 CBD:THC by patient self-titration through sublingual delivery, in comparison to a placebo. After two weeks of treatment, no significant differences in fatigue between the groups were observed (Wade et al. 2003). Conversely, all three groups of CME (THC, CBD, and 1:1 THC:CBD) showed significant improvements in spasticity (Wade et al. 2003). In addition, both the THC and THC:CBD groups demonstrated significant improvements in muscle spasm frequency (Wade et al. 2003).
A systematic review by Nabata et al. (2020) reviewed two other RCTs conducted on people with SCI and reported improvements in spasticity with the use of cannabinoids, specifically THC (Hagenbach et al. 2007; Wilsey et al. 2016). Despite these clinical findings, neither study reported outcomes on fatigue (Nabata et al. 2020). In other clinical populations, such as fibromyalgia, the use of cannabis for fatigue improvement has been under studied as well. Only one RCT showed that THC-rich cannabis oil provides better effects on fatigue scores than a placebo (olive oil) after eight weeks of intervention in 17 women with fibromyalgia (Chaves et al. 2020). In cancer, only one follow-up study from a parent RCT showed that the self-titration of THC/CBD spray or THC spray in inpatients with cancer-related pain experiencing inadequate analgesia despite chronic opioid dosing provided a decrease in different domains, such as fatigue, insomnia, or pain of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (Johnson et al. 2013). Conversely, the use of medical cannabis has yet been studied in neurological populations such as stroke or multiple sclerosis.
Conclusions
There is level 1b evidence (from one RCT: Wade et al. 2003) that cannabis medicinal extracts (CME) had no significant effect on fatigue through sublingual delivery in people with neurological conditions, such as multiple sclerosis and SCI.
