Gastroscopy and H. pylori testing can be performed on the same day. The H. pylori test consists of a urea breath test, an invasive test, a fecal antigen test, and a serum antibody test, and the order of the two needs to be adjusted according to the specific test for H. pylori. The urea breath test is a more accurate test as it requires a capsule to be taken before the test, and then the presence or absence of carbon 13 or carbon 14 labeled carbon dioxide in the exhaled gas is detected to see if the patient is infected with H. pylori. However, gastroscopy requires that no food or water should be consumed prior to the test, and therefore gastroscopy has to be done first, followed by half an hour in the case of a biopsy, and two hours for the case of a biopsy without biopsy, and then the rest of the test can be performed. . The process of invasive testing is to remove a piece of stomach tissue at the same time as gastroscopy and determine whether there is H. pylori infection by rapid urease test, direct smear, histologic examination, and bacterial culture, which is performed at the same time as gastroscopy, with the rapid urease test being the preferred method. The sensitivity and specificity of fecal antigen test is relatively low, but it is simple and fast, and does not conflict with gastroscopy. Serum antibody test can only detect whether the patient has been infected with Helicobacter pylori, but cannot determine whether the infection is now in the stage of infection, and does not conflict with gastroscopy. The above introduction is for reference only, please follow your doctor’s instructions.