Old gas is generally related to dietary factors, and can be caused by gastrointestinal diseases or medications. Excessive consumption of foods high in coarse fiber or fatty foods and carbonated foods can easily cause the occurrence of excessive outgassing. Patients with gastrointestinal disorders, functional dyspepsia, or dysbiosis of intestinal flora or chronic gastrointestinal inflammation are also prone to develop. It also occurs in patients who take certain medications orally, such as commonly used anti-anxiety medications. The condition is also likely to occur in patients with visceral hypersensitivity, or in patients who do not take care of excessive air intake in their diet, which is usually examined without the presence of any organic lesions. In conclusion, first of all, pay attention to your diet, avoid the intake of air-producing foods, develop good eating habits, and if necessary, undergo colonoscopy and other related examinations.