The purpose of this research is to study the level of acid exposure above the gastroesophageal junction and the distal esophagus in patients with reflux symptoms using a capsule type acid measurement system. Patients with reflux symptoms are likely to have more acid reflux just above the junction of the stomach and the esophagus that may help to improve the diagnosis of gastroesophageal reflux disease (GERD). This may help better treat the reflux symptoms.