Objective: To evaluate the clearing and intensity of symptoms of rosacea 60 days after the treatment of Helicobacter pylori infection: Design: Randomized, double-blind, placebo-controlled clinical trial. Setting: The dermatology section of a large multispecialty clinic in the North Central United States. Participants: Men and women older than 25 years with active signs of rosacea who tested positive for H pylori with both the rapid whole blood test and the urea breath test. Intervention: Treatment of H pylori infection with 14-day therapy using clarithromycin, 500 mg orally 3 times a day, and omeprazole, 40 mg orally once a day. Main Outcome Variables: The extent and intensity of rosacea as measured by the number of papules and pustules and the extent and intensity of erythema and telangiectasia. Results: Three hundred twenty patients presented with rosacea. For 50 patients, the results of a urea breath test were positive for H pylori, and 44 patients were enrolled in the study. Rosacea abated in almost all patients, but none were cured. Notably, lessening of rosacea for patients treated for H pylori was not significantly better than for the control cohort. Conclusions: Rosacea abated in most participants in this study, whether they were in the treatment or the control cohort. There was no statistical difference when the results of active treatment were compared with those of placebo. Treating H pylori infection has no short-term beneficial effect on the symptoms of rosacea to support the suggested causal association between H pylori infection and rosacea.