Hello, Carnation, My adult son has been taking Epidiolex for about a year. He also remains on Dilantin and Celontin, both of which he has been on for many years. Before, he was taking Medical Marijuana instead of Epidiolex. The Med. Marijuana was slightly more effective (he had a fewer seizures), but much, much more costly. The Epidiolex does help control his seizures, which occur only when he sleeps or dozes. He was diagnosed with Lennox-Gestault Syndrome a few years ago based on his symptoms (not on his EEG). The main side-effect we have noticed is drowsiness. Best wishes to you if you decide to try it!