Here you go for "medical backround"
Conclusion
There is insufficient evidence to form a reliable conclusion regarding the efficacy of marijuana as an antiepileptic agent.
Despite case reports demonstrating efficacy in reducing seizure frequency and severity, limited clinical studies have been published on its use for this indication. Additionally, the studies conducted were inadequately powered, lacked complete information, and used small sample sizes. There are few studies of long-term administration of cannabis and its safety profile. Currently, legal restrictions on cannabis make it difficult to conduct large-scale clinical trials, as the FDA has classified marijuana as a Schedule I controlled substance. The utility of marijuana for the therapeutic treatment of epilepsy cannot be determined at this time; more large-scale studies are needed that assess the efficacy and safety of treatment with either high CBD-THC ratio marijuana or isolated CBD compounds.
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