Acute gastric stress ulceration: prophylaxis with allopurinol.

: Acute gastric stress ulceration was induced in rats by cold restraint and was not associated with alteration of gastric pH or serum gastrin level. Cimetidine and oral and intravenous allopurinol were prophylactic but allopurinol was more effective in reducing the depth of the lesion and acted without alteration in gastric pH. The efficacy of allopurinol in preventing stress ulceration offers further indirect evidence of the role of ischaemia and oxygen free radical generation in the aetiology of stress ulceration.