Diclofenac is an anti-inflammatory drug that has recently been reported to increase the risk of heart attack. It is used to relieve pain, tenderness, swelling, and stiffness caused by osteoarthritis, rheumatoid arthritis and ankylosing spondylitis. Researchers who reviewed 23 studies involving more than one million people found a 40% increased risk of cardiovascular events, mostly acute heart attacks, in people taking diclofenac. Diclofenac is also sold under the names Cataflam, Voltaren, Clonac, Dichlohexal and Fenac. Diclofenac is currently sold in 62 countries. Researchers from Australia's University of Newcastle found the risk of heart attack and stroke was higher even at common doses of diclofenac. The risk was greatest among those who had heart disease risk factors such as diabetes, smoking or high blood pressure.