Quadruple therapy is the abbreviation for the treatment method used to eradicate H. pylori, which is a combination of four drugs commonly used in a 14-day course of treatment. The commonly used drugs are amoxicillin, clarithromycin, colloidal bismuth and omeprazole, with the usage of amoxicillin at 1g twice a day, clarithromycin at 0.25g twice a day, colloidal bismuth at 150mg four times a day and omeprazole at 20mg two times a day. After 14 days of treatment with this drug, then stop the drug for more than 14 days to do carbon 14 breath test to clarify whether there is still bacterial infection.