The Potential Proconvulsant Effects of Cannabis a Scoping Review.
Cannabis effect on seizure activity is an emerging topic that remains without consensus and merits further investigation. We therefore performed a scoping review to identify the available evidence and knowledge gaps within the existing literature on cannabis product exposures as a potential cause of seizures in humans. A scoping review was conducted in accordance with the PRISMA Extension for Scoping Reviews guidelines. The PubMed and Scopus databases were searched over a 20-year period from the date of the database query (12212020). Inclusion criteria were (1) English language original research articles, (2) inclusion of human subjects, and (3) either investigation of seizures as a part of recreational cannabinoid use OR of exogenous cannabinoids as a cause of seizures. A total of 3104 unique articles were screened, of which 68 underwent full-text review, and 13 met inclusionexclusion criteria. Ten of 11 studies evaluating acute cannabis exposures reported a higher seizure incidence than would be expected based on the prevalence of epilepsy in the general and pediatric populations (range 0.7-1.2% and 0.3-0.5% respectively). The remaining two studies demonstrated increased seizure frequency andor seizure-related hospitalization in recreational cannabis users and those with cannabis use disorder. This scoping review demonstrates that a body of literature describing seizures in the setting of cannabis exposure exists, but it has several limitations. Ten identified studies showed a higher than expected incidence of seizures in populations exposed to cannabis products. Based on the Bradford Hill criteria, delta-9 tetrahydrocannabinol (THC) may be the causative xenobiotic for this phenomenon.