The present invention provides the drugs for preventing gastroesophageal reflux disease with what or preventing gastroesophageal reflux disease recurrence, treating gastroesophageal reflux disease or improvement gastroesophageal reflux disease symptom, wherein existing treatment is not effective for the gastroesophageal reflux disease. 4- [({ 6- [isobutyl group (1； 3- thiazol-2-yl sulfonyl) amino] -2,3- dihydro -1H- indenes -5- base oxygroup) methyl] -3- methyl benzoic acid, its salt or its prodrug prevention gastroesophageal reflux disease or prevention gastroesophageal reflux disease recurrence, treatment gastroesophageal reflux disease or improve gastroesophageal reflux disease symptom in be effective.本發明提供了用於預防胃食管返流疾病或預防胃食管返流疾病復發、治療胃食管返流疾病或改善胃食管返流疾病症狀的藥物，其中就所述胃食管返流疾病而言現有的治療不是有效的。4-[({6-[異丁基(1,3-噻唑-2-基磺酰基)氨基]-2,3-二氫-1H-茚-5-基}氧基)甲基]-3-甲基苯甲酸、其鹽或其前藥在預防胃食管返流疾病或預防胃食管返流疾病復發、治療胃食管返流疾病或改善胃食管返流疾病症狀中是有效的。
