Donald Gross, MD, Assistant Professor of Neurology at the University of Alberta:

“Twenty-one percent of subjects had used marijuana in the past year with the majority of active users reporting beneficial effects on seizures. Twenty-four percent of all subjects believed marijuana was an effective therapy for epilepsy.

Despite limited evidence of efficacy, many patients with epilepsy believe marijuana is an effective therapy for epilepsy and are actively using it.”

June 8, 2004 article, “Marijuana Use and Epilepsy; Prevalence in Patients of a Tertiary Care Epilepsy Center,” published in Neurology

Katherine Mortati, MD, a neurologist at the Comprehensive Epilepsy Center at SUNY Downstate Medical Center:

“Although more data are needed, animal studies and clinical experience suggest that marijuana or its active constituents may have a place in the treatment of partial epilepsy. [In the study] we present the case of a 45-year-old man with cerebral palsy and epilepsy who showed marked improvement with the use of marijuana. This case supports other anecdotal data suggesting that marijuana use may be a beneficial adjunctive treatment in some patients with epilepsy.”

2007 study “Marijuana: An Effective Antiepileptic Treatment in Partial Epilepsy? A Case Report and Review of the Literature,” published in Reviews in Neurological Diseases

John Brust, MD, Professor of Clinical Neurology at Columbia University:

“Marijuana use appeared to be a protective factor against first seizures in men. […] Marijuana contains numerous cannabinoid compounds that differ in convulsant and anticonvulsant properties. Anticonvulsant properties were first noted in the 15th century, yet studies in humans have been few. […]

The authors conclude that heroin use is a risk factor and marijuana use a protective factor for new-onset seizures.“

1990 study “Illicit Drug Use and the Risk of New-onset Seizures,” published in the American Journal of Epidemiology