a. Past or present duodenal and/or gastric ulcer, with or without complications. b. Following resection of gastric cancer. AbstractObjective: To analyze eradication rate and evaluate collateral effects of an existing alternative dosage, comprised of Omeprazole, tetracycline and furazolidone for 7 days in patients with gastric and/or duodenal ulcers and first-degree relatives of family members with a diagnosis of gastric cancer with positive study for Helicobacter pylori (H. pylori) and treatment-naive. Design and location:The out patients from the Clinic of the Gastroenterology Department of the ABC Medical School, Santo Andre, SP-Brazil. Results: 85 patients were included in the study of which 55 completed the treatment. 95% of the patients had an adequate adherence to the treatment. 49% of the patients analyzed by protocol had at least one side effect, with the most common being nausea (24%) and there was no statistical difference between the relation of side effects and lapse of treatment for H. pylori. 5% (3 patients) interrupted the treatment. The eradication rate per protocol (PP) was 96% (95%CI: 84% to 100%) for patients who completed the treatment. Patients and methods: Conclusion:The therapy based on Omeprazole, tetracycline and furazolidone in the dosages proposed represents a good and low-cost alternative to the first-line therapy to eradicate infection by H. pylori in treatment-naive patients in a developing country.