Hi, Dyspepsia, feeling nauseated, are the main symptoms of Gastro-Esophageal Refux disease (GERD) This is mainly due to the incompetency of the sphincter which is present at the junction of esophagus & stomach Stomach secretes acid to help for digestion, but sometimes it may lose its capacity to withhold the normal secretion or excessive secretion of acid. Esophagus do not have the capacity to with hold the regurgitated food from stomach which contains gastric acid - leading to symptom of heart burn. The lesuride is given for so many reasons, one among them is GERD. Investigations like esophago-gastro-duodenoscopy + Barium swallow will help to arrive at a diagnosis. Antacids, Cisapride+antiemetic may be of help till the cause is corrected. All the other medictions per oral to be avoided till then Best Wishes