In a 32-year-old woman with an ulcer that had persisted for more than 13 months despite treatment with the H2 blocker ranitidine, the latter was replaced by the H+K(+)-ATPase inhibitor omeprazole. Treatment with omeprazole also failed to bring about healing of the ulceration which, at times, measured up to 10 cm in diameter. On account of a hemorrhage from the ulcer, a Billroth II resection of the stomach had to be performed. The histological work-up of the surgical specimen confirmed the tentative diagnosis of a secondary ulceration in underlying eosinophilic gastritis established on the basis of the work-up of biopsy material obtained from the ulcer. The reason for the failure of the lesion to respond to the H2 blocker or omeprazole in this case was a diffuse infiltration of the antral wall with eosinophilic granulocytes, and the resulting secondary persistent ischaemic ulceration.