Interest in the use of cannabis for pediatric epilepsy has grown over the last decade, driven in part by media reports of children whose treatment-resistant epilepsy has responded to cannabis [1]. The well-publicized case of Charlotte Figi, whose parents started her on medical cannabis at age 5, is not unique [2], and many parents of children with treatment-resistant epilepsy have reported turning to alternative treatments [3], both with and without the aid of medical professionals. In particular, parents of children with treatment-resistant epilepsy (an inadequate response to two or more adequate trials of antiepileptic drugs [4]), which affects between 28 and 37% of people with epilepsy [5], have expressed great interest in the use of cannabis for the treatment of their children’s epilepsy [3]. Indeed, pediatric treatment-resistant epilepsy has potentially catastrophic consequences, including cognitive delay, behavioral problems, autism, poor quality of life, and early death [6–9].

Despite the recorded medicinal use of cannabis dating back to the second century BCE [10], there has been relatively little research into its effectiveness or safety, likely owing to its illegal status in many jurisdictions. In adults, cannabis has been reported to be effective in the treatment of nausea and vomiting due to chemotherapy, chronic pain, spasticity associated with multiple sclerosis, sleep disorders, and Tourette syndrome, with inconclusive evidence for its use in appetite stimulation in patients with HIV/AIDS, anxiety disorders, and glaucoma [11]. There is relatively little clinical evidence to support the use of cannabis in the treatment of pediatric epilepsy, and there are large discrepancies between the beliefs of health care professionals and the general public with respect to its effectiveness and safety [12]. A 2014 Cochrane review of the use of cannabinoids for the treatment of epilepsy included four small low-quality randomized controlled trials (RCTs), none of which involved children [13]. At the time of this review, the authors concluded that there was insufficient evidence to make reliable conclusions about the efficacy or long-term safety of cannabinoids for the treatment of epilepsy [13]. However, the evidence base in this area is changing rapidly, and recently published studies have suggested a beneficial effect of cannabis in this population [14, 15], although the mechanisms underlying this response are not clear [16].

The use of cannabis in the treatment of pediatric epilepsy is an ideal topic for a living systematic review because it is a priority for decision-making, there is little certainty in the existing evidence base, and there is rapidly accumulating evidence [17]. Living systematic reviews are a relatively new approach to continually updating systematic reviews, with new evidence being incorporated as it becomes available [17]. Unlike traditional systematic review updates, which may be undertaken infrequently, living systematic reviewers search for new studies at a priori-defined intervals and follow a set protocol for determining whether updated analysis and publication are warranted. At present, 37 studies involving the use of various forms of cannabis for the treatment of pediatric epilepsy are registered in ClinicalTrials.gov, suggesting that there will be an abundance of new data in the coming years.

In this living systematic review, we will comprehensively search the published and gray literature for studies that have evaluated the benefits and harms of cannabis for pediatric epilepsy. The results of our review will be of use to parents, clinicians, and policy makers in making treatment decisions for children with epilepsy.