Functional esophageal disease is characterized by functional heartburn, chest pain, dysphagia, dystagmus, and may be accompanied by abdominal pain and diarrhea. Functional heartburn is retrosternal burning-like discomfort and pain. Functional chest pain is non-burning discomfort and pain behind the sternum. Functional dysphagia is the sensation of food adhering to or remaining in the esophagus, or an abnormal sensation of passage through the esophagus after eating. Functional dystagmus is an intermittent or persistent, non-painful sensation of choking or retention of a foreign body in the throat, usually between meals. Often these symptoms last longer and may be accompanied by other symptoms such as abdominal pain, diarrhea, and bloating. Functional esophageal disease symptoms are not caused by GERD and there is no pathologic basis for esophageal dysfunction. There is no pathologic basis for esophageal dyskinesia, and endoscopy does not reveal any lesions. These symptoms are mainly related to psychological factors such as excessive mental tension and stress, and should be treated under the guidance of a doctor.