Breath test mostly refers to urea breath test, and a positive test mostly indicates the presence of H. pylori infection. 1. Breath test is a common way to detect H. pylori infection in clinic, which is categorized into carbon 13 and carbon 14. The patient takes urea labeled with carbon 13 or carbon 14 and exhales, and the result is determined by the amount of the label in the gas. 2. A positive result usually indicates the presence of H. pylori infection, but false positives due to factors such as eating cannot be ruled out. Patients who are clearly infected with H. pylori need prompt anti-H. pylori treatment. 3. Clinically, quadruple therapy is commonly used, i.e. two antibiotics (metronidazole, tinidazole, clarithromycin, furazolidone, tetracycline, etc.) together with a proton pump inhibitor (omeprazole, lansoprazole, pantoprazole, rabeprazole, etc.) and a bismuth agent (bismuth potassium citrate, etc.). It is recommended that patients with a positive breath test use medication against H. pylori infection as prescribed by their physician after ruling out false positives.