A method of treating or preventing a heart condition selected from the group consisting of heart failure, myocarditis, toxicity caused by anti-cancer therapies, acute pericarditis, cardiac sarcoidosis, inflammatory cardiomyopathy, and atherosclerosis in a subject in need thereof, the method comprising administering an effective amount of cannabidiol (CBD) to the subject, wherein the administration of the CBD effects (i) a reduction of a level of B-type natriuretic peptide (BNP), (ii) a reduction of a level of cluster of differentiation 69 (CD69), (iii) an increase in a level of cytokine interleukin 10 (IL10), or (iv) a combination of any of (i) to (iii) in the subject.