Pericarditis is the inflammation of a sac that surrounds the heart. It can occur after cardiac surgery; from viral infections, tuberculosis, cancer, or an autoimmune disease; or, commonly, for no identifiable reason. Pericarditis usually causes pain and sometimes it causes life-threatening fluid accumulation around the heart. Although patients benefit from treatment with anti-inflammatory drugs (such as aspirin, ibuprofen, or a steroid), pericarditis frequently recurs. Recurrences are a troublesome complication of pericarditis, occurring in about one third of patients with acute pericarditis and up to 50% of patients with a first recurrence. Some patients have been treated with another drug, colchicine, although data from well-done clinical trials are limited.