Highly purified cannabidiol oral solution was approved by the FDA for the treatment of seizures associated with several specific epilepsy syndromes (Lennox Gastaut Syndrome, Dravet Syndrome, and Tuberous Sclerosis Complex). In addition to the pivotal phase III clinical trials which led to this approval, there were multiple concomitant open label expanded access programs in several states investigating the use of this same product on treatment resistant epilepsy. As one of the investigators of one of the largest expanded access programs, Dr. Gaston will discuss her experiences conducting this study, the results from the open label studies and how they add to the body of knowledge, Further, she will discuss how her experience has influenced her clinical practice of prescribing this product to patients with epilepsy since the FDA approval.