Friedman D, Devinsky O. Cannabinoids in the treatment of epilepsy. N Engl J Med 2016;374(1):94-5 Abstract

Why was this study conducted?

Although a number of new drugs to control epilepsy have been developed over the past two decades, up to 30% of patients continue to have seizures and better treatments with fewer side effects are needed. To determine whether cannabis might be a good treatment option, the authors reviewed the action of cannabinoids in the brain and human studies conducted between 1949 and 2015 of isolated oral cannabinoids, oral cannabis extracts and smoked cannabis in people with epilepsy.

What does this study add?

The authors conclude that preclinical and preliminary data make it reasonable to think cannabis could be helpful in treating epilepsy, but there is insufficient research data to date with patients to make solid conclusions. Despite this lack of scientific evidence, some people affected by epilepsy are convinced that because it is “natural” cannabis should be safe and effective. The gap between patient beliefs (expectancies) and scientific evidence confounds cannabinoid research and should be addressed.

Is there anything else I should know?

This is not a formal systematic review, insofar that there is no statement of search terms, how articles were selected for inclusion, etc. Of the 15 human studies summarized, 12 had fewer than 20 participants, with six being case reports of individual patients. There was only one randomized controlled trial and it was limited to 12 patients.

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 Medical Advisor Dr. Ramesh Zacharias, MD, a clinician with expertise in chronic pain. There are no conflicts of interest. Questions regarding this piece should be directed to Dr. Ramesh Zacharias (