Antral G cell hyperfunction (AGCH) is a rare condition, often associated with severe duodenal ulcer disease poorly responsive to medical therapy. Up to now, no studies have been designed to investigate a possible role of medical treatment in the management of this syndrome. In this study we treated 9 AGCH patients with duodenal ulcer, unhealed with the prolonging standard doses of H2 antagonists (300 mg/day ranitidine or 800 mg/day cimetidine), with a nonantacid therapy, tripotassium dicitrato bismuthate (TDB). 6 out of 9 patients showed a complete healing after 8 weeks of treatment. The healing was irrespective to eradication of Campylobacter pylori. After 9 weeks' suspension of H2 blockers basal gastrin levels decreased significantly by 31.5%, whereas peak meal-stimulated levels, although decreased in 6 out 9 patients, were not significantly affected by the withdrawal of the H2 antagonists. Nonantisecretory therapy seems to be an efficacious alternative in the management of AGCH patients.