Adverse effects of quadruple drug therapy include gastrointestinal reactions that may lead to loss of appetite. Quadruple therapy is mainly applied to the radical treatment of Helicobacter pylori, which refers to the method of four-drug combination therapy including two antibiotics combined with proton pump inhibitor and bismuth agent. Antibiotics are commonly used such as amoxicillin, clarithromycin, metronidazole, tinidazole, etc.; proton pump inhibitors are commonly used such as omeprazole, rabeprazole, etc.; and bismuth preparation includes bismuth citrate and bismuth pectinate. The common adverse reactions of quadruple therapy are mainly caused by the four drugs, mainly including rash, abdominal distension, abdominal pain, indigestion, grayish-black stools, dizziness, headache, neutropenia, etc. Therefore, loss of appetite may occur during the use of medication, and continue to observe can be, without special treatment. During the treatment period, patients need to avoid stopping or skipping the medication on their own, and if they do experience significant discomfort, they should seek prompt medical evaluation to determine whether a change in medication is necessary.