This study showed that 86% of 272 patients with refractory epilepsy experienced some benefit from the use of artisanal (non-standardized) cannabis preparations. This comes from retrospective data on patients with medically refractory epilepsy of mixed etiologies from Washington, California and Maine.
Cannabis (marijuana) provided 100% reduction of seizures for 10% of the users, a 76-99% reduction of seizures for 28%, a 51-75% reduction of seizures for 17%, a 26-50% reduction of seizures for 18%, a 1-25% reduction of seizures for 15%, and no improvement for 14%. Seizures increased in 4%. Other side effects were mild and well tolerated.
Overall, these preparations of CBD, CBD plus THC, and CBD plus THCA demonstrate that epilepsy patients may benefit from usage.