Sixty subjects were carefully interrogated and repeatedly endoscoped with a view to studying the effect of sucralfate on healing and recurrence of duodenal ulcer disease. Degree of bulbar deformity was noted during each endoscopy. During the trial it appeared that deformity progressed more rapidly in late onset subjects (onset at or above 30 years of age). In eight subjects deformity became gross over a period of three years. Seven of them belonged to the late onset subgroup. Two subject had large ulcers and both belonged to the late onset subgroup, one had rapidly progressive disease. Out of six subjects with multiple ulcers four belonged to the late onset subgroup, two of the later had rapidly progressive disease.