Clarithromycin and omeprazole can be taken at the same time if the condition requires it and there are no contraindications. Clarithromycin is an antibiotic used for anti-infective treatment. Adverse reactions include oral odor, abdominal pain, diarrhea, nausea, vomiting, headache, hypersensitivity, and transient elevation of serum aminotransferase. It is contraindicated in severe hepatic injury, hydroelectrolyte disorders, those taking terfenadine, cardiac arrhythmias, bradycardia, prolonged Q-T interval, ischemic heart disease, heart failure, and hypersensitivity. Omeprazole is a proton pump inhibitor for gastric ulcer, duodenal ulcer, stress ulcer, reflux esophagitis and gastrinoma. Common adverse reactions are diarrhea, headache, nausea, abdominal pain, bloating, increased serum aminotransferase, rash, dizziness, somnolence, and insomnia. It is contraindicated in those who are allergic to the product and those with severe renal insufficiency. Clarithromycin and omeprazole’s drug components have no drug conflicts or drug reactions, and can be used at the same time if the condition requires it. For example, people infected with Helicobacter pylori and treated with quadruple therapy against Helicobacter pylori can take clarithromycin and omeprazole at the same time. Clarithromycin and omeprazole should be used under the guidance of a doctor, and should not be taken on their own.