Background: A better appreciation of the causal relationship between Helicobacter pylori infection and peptic ulcer disease and the benefit conferred by curing this infection has led to the recommendation that all patients with duodenal ulcer disease receive anti-H. pylori treatment. Multi-drug regimens, including bismuth, metronidazole and tetracycline or amoxycillin with an antisecretory agent, are successful in >90% of treated patients but the emergence of metronidazole-resistant H. pylori has begun to limit their effectiveness. Design: The search for the optimal anti-H. pylori treatment has focused on simplifying the regimen (to decrease adverse drug-related events and increase patient compliance), while retaining the excellent clinical results of the traditional multi-drug regimens. This article reviews the data concerning clarithromycin for treatment of H. pylori infections. Results: Numerous evaluations have shown that clarithromycin has desirable attributes for anti-H. pylori treatment: clarithromycin is resistant to gastric acid, penetrates in high concentrations into gastric tissue and mucus, shows excellent antimicrobial activity against H, pylori, results in a high cure rate when used in two- and three-drug combinations, is associated with a low incidence of acquired H. pylori resistance and is well tolerated. Successful clarithromycin therapies include clarithromycin + omeprazole, clarithromycin + amoxycillin, or clarithromycin + omeprazole + tinidazole or metronidazole, and clarithromycin triple therapy. Conclusion: Clarithromycin may become an integral component of anti-H. pylori therapy.