Additional Study Information: The main purpose of the study is to evaluate if treatment with CardioRX will prevent pericarditis recurrences after the therapy with IL-1 blocker (medication to reduce inflammation) has been stopped. You are being asked to join the study because you have recurrent pericarditis. Pericarditis is inflammation of the percardium (double layer sac that surrounds the heart). The pericardium allows your heart to move freely with each heartbeat. Recurrent pericarditis is an episode of pericarditis that occurs after a symptom-free period of more than 4 weeks after the last episode. CardioRX is the study dug, a cannabidiol (CBD) oral solution taken by mouth for the treatment of your condition. This oral solution has not been approved by the Food & Drug Administration (FDA). Involvement is expected to last approximately 6.5 months. You will be asked to complete a few study-related assessments such as physical exam, imaging, blood draw, Electrocardiogram (ECGs) and a suicide questionnaire. You will be randomized to either receive CardioRX or a placebo (looks like the medication but has no active ingredients). You will have a 50/50 chance of getting the study drug or placebo. This study is designed to compare the study drug to a placebo, with participants randomly assigned to different groups. Neither the participants nor the researchers will know who is receiving the real treatment. The study will run for approximately 26 weeks and during this time you will have 10 scheduled visits with your study team at the clinic. You will receive study treatment from Day 1 to the end of Week 24.