There are three main side effects of H. pylori treatment: 1, there will be gastrointestinal adverse reactions, whether you choose clarithromycin or amoxicillin, there will be gastrointestinal discomfort symptoms, accompanied by abdominal pain, nausea, vomiting and diarrhea and other symptoms, all because of the adverse reactions that occur after taking the drug, and if the drugs are stacked together, the symptoms of gastrointestinal discomfort more obvious. 2, in the use of drugs The treatment of Helicobacter pylori will also lead to a gradual increase in transaminases, so it is recommended that after 10-14 days of treatment should be suspended for a period of time. 3, after taking the oral cavity will also be accompanied by a significant sense of odor, probably because of the adverse reactions caused by taking drugs, but also need to stop taking drugs as soon as possible.