Omeprazole triple therapy has been shown to produce Helicobacter pylori eradication rates of up to 96% in patients with current or recent peptic ulceration, Such therapy is also now being used without endoscopy in H. pylori-positive patients who may have an inactive ulcer or dyspepsia, and in whom their effectiveness has been less well documented. Compliance is an important variable affecting H, pylori eradication; with I-week omeprazole triple therapy, however, compliance is uniformly high, and this allows more detailed analysis of other causes of treatment failure. The strains of H, pylori in patients with functional dyspepsia may be associated with a lower degree of inflammation. Two new, large studies (DU-MACH and GU-MACH) have therefore looked at the impact of inflammation on H, pylori eradication. Polymorph infiltration in the antrum of patients with inflammation of grades 2/3 was associated with a significantly higher eradication rate when compared with inflammation of grades 0/1, Inflammation may be important for a number of reasons, including degradation of the mucus and epithelial layers (which may allow better penetration of charged antibiotics from the gastric lumen) and altered vascular and epithelial permeability (which may allow better systemic delivery of drugs), Alternatively, inflammation may be a marker for more aggressive H, pylori subtypes, which are also more vulnerable to antibiotic therapy. Eur J Gastroenterol Hepatol 11 (suppl 2):S25-S28 (C) 1999 Lippincott Williams & Wilkins.