Levofloxacin Concomitant Versus Levofloxacin Sequential

Inclusion Criteria: * Patients are aged greater than 18 years old who have H. pylori infection diagnosed by any of following three methods: * Positive rapid urease test (CLOtest). * Histologic evidence of H. pylori by modified Giemsa staining. * Positive 13C-urea breath test. without prior eradication therapy and are willing to receive therapy. Exclusion Criteria: * Children and teenagers aged less than 18 years. * Previous eradication treatment for H. pylori. * Patients who took any drug, which could influence the study results such as proton pump inhibitor, H2 blocker, mucosal protective agent and antibiotics. * History of gastrectomy. * Gastric malignancy, including adenocarcinoma and lymphoma, * Previous allergic reaction to antibiotics (Amoxicillin, Tinadizole, * Doxycycline,Bismuth subsalicylate,) and prompt pump inhibitors (Es- omeprazole). * Contraindication to treatment drugs. * Pregnant or lactating women. * Severe concurrent disease. * Liver cirrhosis.