Epidiolex Trial for Presymptomatic Treatment of Sturge-Weber Syndrome

Inclusion Criteria: * Clinical diagnosis of Sturge-Weber Syndrome. * Age 1 to 18 months of age, inclusive. * Neuroimaging demonstrating involvement of 3 or more lobes, or bilateral involvement. * No history of seizures. * Patient's parent or legal guardian provides written informed consent prior to treatment initiation. Exclusion Criteria: Any severe and/or uncontrolled medical conditions at randomization including, but not limited to the following: * Liver disease such as cirrhosis, decompensated liver disease, and chronic hepatitis (i.e. quantifiable HBVDNA and/or positive HbsAg, quantifiable HCV-RNA). Specifically the patient should not have either AST or ALT more than 1.5 times the upper limit of normal. The Child- Pugh Score must be A (mild) which is a score of 5-6 (minimum/normal score=5). Child-Turcotte-Pugh (CTP) Calculator - Clinical Calculators - Hepatitis C Online (uw.edu) * Uncontrolled diabetes as defined by fasting serum glucose \> 1.5 ULN * Active (acute or chronic) or uncontrolled severe infections * Active, bleeding diathesis * Any other neurological diagnosis that increases the risk of seizure or neurodevelopmental disability. * Patients who have had a major surgery or significant traumatic injury within 4 weeks of study entry, patients who have not recovered from the side effects of any major surgery (defined as requiring general anesthesia), or patients that may require major surgery during the course of the study. * Prior treatment with any investigational drug or use of any other cannabis product within the preceding 4 weeks prior to study entry. * Use of aspirin. * Allergic reaction/hypersensitivity to Epidiolex or other forms of cannabidiol. * Concern for non-compliance to medical regimens, or concern that the patient will not be able to complete the entire study, whether due to reliability or logistical barriers. This includes those in foster care, or those unable to keep follow-up appointments, maintain close contact with Principal Investigator, or complete all necessary studies to maintain safety. * Use of any seizure medication (whether for seizures or any other reason) (e.g. valproate, clobazam). * Use of chronic medications other than a multi-vitamin and/or vitamin D supplements.