The breath test is done by blowing through the mouth. Clinical breath test generally refers to carbon 13 or carbon 14 breath test, mainly used to check the stomach Helicobacter pylori bacteria, the test needs to be unfed water for two hours before the test. Carbon 13 breath test, the patient first blowing into the pre-dose bag, then oral urea carbon 13 capsule, half an hour later, and then blowing into the post-dose bag, and then use the equipment to detect the value. For the carbon 14 breath test, the patient first takes a urea carbon 14 capsule by mouth, then blows into the gas collection bottle after half an hour, and finally the device is used to check the value. So the breath test is required to blow with the mouth to complete, daily if abdominal pain, bloating, belching and other discomforts, it is recommended to consult a doctor in time, so as not to delay the condition.