Gastroesophageal reflux disease (GERD) occurs when acid regurgitates from the stomach to the esophagus, causing heartburn, dry cough, acidic taste in the mouth. The condition occurs due to insufficiency of the sphincter muscle that is supposed to prevent the passage of acid between the stomach and esophagus. Gastroesophageal reflux is common during the night when patients lie down. It commonly affects sleep and should be treated.