BACKGROUND: Eradication of Helicobacter pylori in patients with functional dyspepsia continues to be a matter of debate. We studied eradication effects on symptoms and quality of life of primary care patients. METHODS: Helicobacter pylori -positive adult patients with functional dyspepsia meeting the Rome III International Consensus criteria were randomly assigned to receive omeprazole, amoxicillin trihydrate, and clarithromycin, or omeprazole plus placebo for 10 days. Endoscopy and H pylori tests were performed at screening and at 12 months. Outcome measures were at least 50% symptomatic improvement at 12 months using a validated disease-specific questionnaire (primary end point), patient global assessment of symptoms, and quality of life. RESULTS: We randomly assigned 404 patients (78.7% were women; mean age, 46.1 years); 201 were assigned to be treated with antibiotics (antibiotics group) and 203 to a control group. A total of 389 patients (96.3%) completed the study. The proportion of patients who achieved the primary outcome was 49.0% (94 of 192) in the antibiotics group and 36.5% (72 of 197) in the control group (P = .01; number needed to treat, 8). In the patient global assessment of symptoms, 78.1% in the antibiotics group (157 of 201) answered that they were better symptomatically, and 67.5% in the control group (137 of 203) said that they were better (P = .02). The antibiotics group had a significantly larger increase in their mean (SD) Medical Outcomes Study 36-Item Short Form Health Survey physical component summary scores than the control group did (4.15 [8.5] vs 2.2 [8.1]; P = .02). CONCLUSION: Helicobacter pylori eradication provided significant benefits to primary care patients with functional dyspepsia. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00404534.