Indometacin (INN and BAN) or indomethacin (AAN, USAN and former BAN) is a nonsteroidal anti-inflammatory drug (NSAID) commonly used as a prescription medication to reduce fever, pain, stiffness, and swelling from inflammation. It works by inhibiting the production of prostaglandins, molecules known to cause these symptoms. It is marketed under more than twelve different trade names. As of 2015 the cost for a typical month of medication in the United States is less than 25 USD.