Bad breath caused by the stomach and intestines can be due to gastritis, enteritis, peptic ulcers, or Helicobacter pylori infection. It is usually curable. If the bad breath is caused by gastrointestinal diseases, it is necessary to actively treat the gastrointestinal and improve the diet, and the patient can take drugs to promote gastrointestinal dynamics, such as mosapride, domperidone, etc., so as to improve the symptoms. If you suffer from gastritis and gastric ulcer, you should also apply acid-suppressing drugs and gastric mucosal protectants, such as omeprazole and magnesium aluminum carbonate. In addition, daily attention should be paid to diet, eat more light and easy to digest food, avoid eating greasy, spicy and other stimulating food. In addition, patients should also check whether there is Helicobacter pylori infection, you can go to the hospital for breath test, if there is Helicobacter pylori infection, you also need to add antibiotics, applying quadruple drugs for eradication, such as omeprazole, bismuth potassium citrate, amoxicillin, clarithromycin. In addition to medication for gastrointestinal diseases, patients can also improve bad breath temporarily by brushing their teeth well to freshen their mouth. Patients should keep moderate exercise in general, so as to promote digestion and intestinal peristalsis.