GERD or Gastroesophageal reflux disease is a common name for a variety of problems that present with symptoms of indigestion including acid brash and heart burn, upper abdominal pain and bloating, atypical chest pain or vomiting and nausea. Some patients report a reflux of undigested food also. It may be caused by increased acid production, mechanical valve problem between the stomach and esophagus (food pipe), or bile acid issues. A specialist can diagnose and treat this disease.