Quadruple therapy is mostly chosen for the treatment of Helicobacter pylori, and the main drugs include omeprazole, clarithromycin, amoxicillin, metronidazole, and bismuth potassium citrate. Quadruple therapy is one of the most commonly used methods for the treatment of H. pylori, i.e., one acid-suppressing drug, two antibiotics, one bismuth agent, etc. 1. Acid-suppressing drugs: most of them use proton pump inhibitors, and the main drugs are omeprazole, pantoprazole, lansoprazole, rabeprazole and so on. Patients who are allergic to the drugs are prohibited. 2. Antibiotics: commonly used antibiotics include amoxicillin, clarithromycin, metronidazole, furazolidone, quinolones, tetracycline and so on, usually choose two kinds of combination. Patients who are allergic to antibiotics should take appropriate antibiotics to avoid anaphylactic shock and so on. 3. Bismuth: commonly used ones include bismuth pectin, bismuth potassium citrate, etc.. Pregnant women, liver and kidney insufficiency and those who are allergic to the drugs are prohibited. All of the above drugs should be taken under the guidance of a doctor, and should not be used blindly on their own to avoid adverse effects.