Turna J, Syan SK, Frey BN, Rush B, Costello MJ, Weiss M, MacKillop J. Cannabidiol as a novel candidate alcohol use disorder pharmacotherapy: a systematic review. Alcohol Clin Exp Res 2019; 43(4):550-563 (full text at Wiley or PMC)

Why was this study conducted?

Alcohol is the most common drug used by Canadians and alcohol use disorders (AUD) are a challenge for clinicians and patients. Although there are a number of existing AUD pharmacotherapies, suboptimal treatment outcomes are common and new approaches are needed. To determine if the cannabinoid cannabidiol (CBD) can be helpful in treating AUD, researchers conducted a systematic literature review of the preclinical (8 rodent studies, most of which administered CBD transdermally or by injection, and 1 in vitro cell culture study) and early clinical studies (3 small studies with healthy adult volunteers who were given oral CBD either alone or with alcohol). 

What does this study add?

In both rodents and the cell culture models, CBD had a neuroprotective effect and in rodent models attenuated alcohol-induced hepatotoxicity. In rodent models, CBD was observed to have beneficial effects on behaviours associated with alcohol motivation and relapse, such as cue- and stress-elicited alcohol seeking, alcohol self-administration, withdrawal-induced convulsions, and impulsive discounting of delayed rewards. In the 3 human studies, CBD did not decrease alcohol intoxication but was not associated with the same detrimental cognitive effects as either alcohol or THC, suggesting that it could be a well-tolerated alternative.

Is there anything else I should know?

The studies reviewed establish a rationale for the use of CBD in the treatment of AUD but also illustrate the limitations in the current research literature. More human laboratory and clinical studies, with an emphasis upon integrated bench-to-bedside studies, are needed to provide a more comprehensive basis for clinical decision-making.

Author Details

The latest scientific evidence on this topic was reviewed by the Centre's leadership team. This research summary is written by Corinne Hodgson, DHealth, assessed for accuracy by Dr. James MacKillop, PhD. There are no conflicts of interest. Questions regarding this piece should be directed to Dr. James MacKillop (jmackill@mcmaster.ca).