H. pylori does not usually cause bad breath, but H. pylori infection may cause bad breath because H. pylori in the gastrointestinal tract or the mouth can secrete urease, and the decomposition of urease will produce carbon dioxide and ammonia, and ammonia is a rather unpleasant smell that can be excreted from the esophagus and the mouth, so many patients with H. pylori infection will have bad breath. Usually this bad breath is not effectively relieved by oral cleansing and needs to be relieved by eradication of H. pylori. There are several ways to relieve bad breath in general: 1, dental cleaning: through ultrasonic cleaning, can reduce the oral cavity of H. pylori, so as to avoid the breeding and reproduction of H. pylori in the mouth, and at the same time can avoid bad breath caused by dental calculus or oral inflammation; 2, the application of drugs: after the eradication of H. pylori can make effective relief of bad breath, the general choice of quadruple therapy, that is, two antibiotics combined with proton pump inhibitors Bismuth agent together. In addition, drugs that promote gastrointestinal motility, such as domperidone, mosapride, etc., can be used under the guidance of a doctor to improve the gastrointestinal tract indigestion, which can avoid bloating and belching due to incomplete digestion of food, which can cause bad odor.