Inflammation of the pancreas. Symptoms of acute and chronic pancreatitis are similar and can include pain, nausea and vomiting, and a swollen abdomen. Gallstones are the most common cause of acute pancreatitis. Chronic, heavy alcohol use is a common cause of both acute and chronic pancreatitis. Pancreatitis may also be caused by use of certain antiretroviral (ARV) drugs or an opportunistic infection.