The aim of this pilot study was to evaluate the efficacy and safety of lansoprazole plus clarithromycin for eradication of Helicobacter pylori. A total of 26 patients with H. pylori infection were randomised to receive clarithromycin, 500 mg t.i.d. for 14 days, plus either lansoprazole, 30 mg o.m., (group L30, n = 13) or lansoprazole, 30 mg b.i.d., (group L60, n = 13). H. pylori status was determined pre-treatment and four to six weeks after completion of the study medication by histology and 13C-urea breath test. Two patients were unable to complete the course of medication. Of the remaining 24 patients, 14 (58%) successfully eradicated H. pylori--8/12 (67%) patients in group L30 and 6/12 (50%) in group L60. Side-effects were experienced by 17/26 (65%) of patients, most commonly a taste disturbance. The results from this pilot study suggest that dual therapy with lansoprazole plus clarithromycin is only a moderately effective regimen for eradicating H. pylori.