Fasting or more than 2 hours after a meal is required for a Carbon 14 Blowout. Failure to fast or more than 2 hours after a meal may affect the accuracy of the Carbon 14 test results. Carbon 14 is a highly sensitive, specific, fast, easy, safe and inexpensive way to detect H. pylori. It is based on the principle that H. pylori produces the highly active enzyme urease, which breaks down urea into ammonia and carbon dioxide. When carbon 14-labeled urea is taken, the carbon dioxide labeled with carbon 14 can be traced, proving the presence of infection. If the carbon 14 blow is not done on an empty stomach or more than 2 hours after a meal, interference from other foods cannot be eliminated, affecting the accuracy of the test. Therefore, a carbon 14 breath should be done on an empty stomach or more than 2 hours after a meal. In addition, it should be noted that the use of antibiotics and other drugs should be avoided for one month. It is recommended that you consult your doctor for specific precautions to prepare for the test to avoid delaying the test.