Before doing the H. pylori test you can brush your teeth, brushing does not affect the test results, because H. pylori is mainly present in the human stomach cavity, which can cause infectious diseases of the stomach, the main test for H. pylori is to understand the situation of HP infection in the stomach, the common test methods are carbon 13 or carbon 14 breath test, there is also a venous blood test for H. pylori antibodies, or electronic gastroscopy to take Gastric mucosal biopsy for rapid urease assay. The most recommended of the above three methods is the breath test, which is a non-invasive test, and does not require an electronic gastroscope, and the accuracy rate is very high, so it is often used as the preferred test method, requiring an empty stomach or more than 2 hours after a meal to do the breath test, so there is no effect on whether or not to brush your teeth.