The breath test to detect H. pylori requires fasting. The principle of the breath test is that H. pylori can break down urea to produce carbon dioxide. During the test, the patient swallows urea labeled with the isotope carbon 13 or carbon 14, and if the patient is infected with H. pylori, the swallowed urea breaks down to produce ammonia and carbon dioxide containing carbon 13 or carbon 14. The exhaled breath of the patient is collected and instrumented to detect the presence of H. pylori infection. Carbon 13 and carbon 14 breath test, the test does not rely on endoscopy, is painless for the patient, simple and convenient, and highly accurate, but its results are easily affected by antibiotics, bismuth, and acid-suppressing drugs. The test requires fasting and should be performed on an empty stomach for more than six hours; eating may affect the accuracy of the test results. If discomfort occurs, it is recommended to consult a doctor in time and carry out targeted treatment under the guidance of the doctor, do not take medication on your own to avoid delaying your condition.