Background:Proton pump inhibitor based combination therapy is one standard strategy for Helicobacter pylori eradication. Aim:To compare the eradication and duodenal ulcer healing efficacy of two 2-week, single dose, lansoprazole based combination therapies. Methods:Healthy adult patients with endoscopically confirmed, H. pylori associated duodenal ulcer disease (3 mm > ulcer < 20 mm) were eligible for the study. All patients received a 14 day course of lansoprazole 30 mg o.m., and were randomized to receive either 7 or 14 days of amoxycillin 1 g b.d. and clarithromycin 500 mg b.d. Patients were endoscoped at entry and 14–17 days later. Symptomatic, unhealed patients received a further 14 days of therapy with lansoprazole 30 mg o.m. Eradication was confirmed a minimum of 28 days after cessation of all therapy by urease reaction and histological assessment of gastric body and antral biopsies (three biopsies each site). Results:Sixty-two patients were randomized to a treatment arm, of which 58 could be included in an intention-to-treat and key-point-available analysis. H. pylori eradication rates were identical, at 93% (95% CI: 73–98% (1 week), 78–99% (2 week)). In the combined group, all but 13 ulcers were healed at 2 weeks; six required further therapy because of symptoms, while six of the seven asymptomatic patients went on to heal. Conclusion:An eradication regimen, based on a 2-week course of single dose lansoprazole with 1 week of antibiotic co-therapy, is effective in eradicating H. pylori, while the 2 weeks of acid suppression is usually effective in duodenal ulcer healing. [ABSTRACT FROM AUTHOR]