 Medical researchers have confirmed what some desperate parents have been claiming for years—that a nonpsychoactive component of marijuana known as cannabidiol (CBD) can reduce epileptic seizures in some children. The study, published today (May 24) in the New England Journal of Medicine, is among the first to provide solid, clinical evidence to support a form of treatment that is becoming fairly widespread with the advent of medical marijuana, but which remains largely unregulated. “This study clearly establishes cannabidiol as an effective anti-seizure drug for this disorder and this age group," says principal investigator Orrin Devinsky, director of the Comprehensive Epilepsy Center at New York University Langone Medical Center. Epidiolex is a 99 percent cannabidiol preparation made by the U.K.-based company, GW Pharmaceuticals, which funded the study. But unlike tetrahydrocannabinol (THC), which is the main psychoactive chemical in marijuana, CBD does not get users "high." [3 More States Legalize Recreational Marijuana Use: How the Map Looks Now] 
 
 “We desperately need other studies like this in other forms of epilepsy and using other cannabis preparations. Whereas there was a statistically and clinically significant median reduction in convulsive seizures of 39 percent in the treated group, only three of the 52 patients receiving cannabidiol became completely seizure-free. Those patients who took CBD showed some side effects, including diarrhea, vomiting, fatigue and abnormal results on liver-function tests. After the trial caregivers of participants in both the placebo and experimental groups were given the option of continuing treatment with cannabidiol in what is called an open-label extension of the study. She had her first seizure at six months and at 18 months suffered a severe reaction to an epilepsy drug that left her with profound cognitive deficits. "Just because it's natural and just because there may be anecdotal support from people, doesn't mean it's effective and safe." No one really knows yet how cannabidiol reduces seizures in Dravet, but Devinsky says the leading theory is that the cannabidiol binds to a receptor in nerve cells called GPR55, modulating the calcium activity and excitability of the cells. The new study was a randomized, double-blind, placebo-controlled trial — a study design that's considered the gold standard for clinical research.
– Backing up what some parents have been claiming for years, researchers are now hailing a compound in marijuana as a "game-changing medication" for epilepsy. Based on testimonials from parents, Orrin Devinsky of NYU's Comprehensive Epilepsy Center set out to find proof that epilepsy could be treated with cannabidiol (CBD)—and he says he did. In a 14-week study, 60 kids and teens with a severe form of epilepsy known as Dravet syndrome were given doses of CBD and saw their number of monthly convulsive seizures fall from 12 on average to about six, reports Live Science. Three patients saw their seizures stop entirely, the researchers say in the New England Journal of Medicine. One downside: Almost all patients who took CBD reported side effects, including vomiting and diarrhea, per Scientific American. (CBD doesn't get users high.) But 62% of caregivers said the condition of the child in their care improved overall. That's compared to 34% of caregivers of children who took a placebo, who went from having about 15 monthly seizures to about 14. Given this study and others, Devinsky says it's "medieval" that marijuana is deemed a Schedule I substance under the Controlled Substances Act. Drugs in this category have "no currently accepted medical use," according to the Drug Enforcement Administration, but that's "simply untrue," he says. "To put CBD as a Schedule I drug violates scientific data and common sense." (More on CBD and epilepsy here.)