A Systematic Review of the Effectiveness of Medical Cannabis for Psychiatric, Movement and Neurodegenerative Disorders

Abstract

The discovery of endocannabinoid’s role within the central nervous system and its potential therapeutic benefits have brought forth rising interest in the use of cannabis for medical purposes. The present review aimed to synthesize and evaluate the available evidences on the efficacy of cannabis and its derivatives for psychiatric, neurodegenerative and movement disorders. A systematic search of randomized controlled trials of cannabis and its derivatives were conducted via databases (PubMed, Embase and the Cochrane Central Register of Controlled Trials). A total of 24 reports that evaluated the use of medical cannabis for Alzheimer’s disease, anorexia nervosa, anxiety, dementia, dystonia, Huntington’s disease, Parkinson’s disease, post-traumatic stress disorder (PTSD), psychosis and Tourette syndrome were included in this review. Trial quality was assessed with the Cochrane risk of bias tool. There is a lack of evidence on the therapeutic effects of cannabinoids for amyotrophic lateral sclerosis and dystonia. Although trials with positive findings were identified for anorexia nervosa, anxiety, PTSD, psychotic symptoms, agitation in Alzheimer’s disease and dementia, Huntington’s disease, and Tourette syndrome, and dyskinesia in Parkinson’s disease, definitive conclusion on its efficacy could not be drawn. Evaluation of these low-quality trials, as rated on the Cochrane risk of bias tools, was challenged by methodological issues such as inadequate description of allocation concealment, blinding and underpowered sample size. More adequately powered controlled trials that examine the long and short term efficacy, safety and tolerability of cannabis for medical use, and the mechanisms underpinning the therapeutic potential are warranted.

Antioxidative and Anti-Inflammatory Properties of Cannabidiol

“…Thus, the action of CBD as a phytocannabinoid may support the biological activity of the endocannabinoid system. CBD has recently been shown to modulate the endocannabinoid system activity by increasing anandamide (AEA) levels [5], which can affect cannabinoids signaling, including their interaction on cannabinoid receptors [57]. However, it is known that the peroxisome proliferator-activated receptor alpha (PPAR-α), for example, activated by endocannabinoids, directly regulates the expression of antioxidant enzymes such as superoxide dismutase by interacting with their promoter regions [58].…”

“…It is non-psychoactive, but has many beneficial pharmacological effects, including anti-inflammatory and antioxidant effects [4]. In addition, it belongs to a group of compounds with anxiolytic, antidepressant, antipsychotic, and anticonvulsant properties, among others [5]. The biological effects of cannabidiol, including the various molecular targets, such as cannabinoid receptors and other components of the endocannabinoid system, with which it interacts, have been extensively studied.…”

Interaction between warfarin and cannabis

“…1 Further, medical use of cannabis is on the rise, as it has been proposed to provide some relief for pain disorders, vomiting and nausea. [2][3][4] Systematic assessment of the literature provides little guidance, with no or insufficient evidence for most pain conditions except for neuropathic pain. The evidence supporting the latter use remains unimpressive.…”

Cannabinoids in the Older Person: A Literature Review

“…Two systematic reviews have also been published in this field [23,28]. When pooled, these reviews included five studies which assessed dronabinol; 1 assessing nabilone; 2 THC.…”