Effect of cimetidine on the regeneration of the gastric mucosa around a peptic ulcer.

Histological changes in gastric ulcers during the healing process with cimetidine treatment were compared with those seen with conventional treatment. Healing time of the ulcers was clearly shortened, and the regeneration of the marginal mucosa of gastric ulcers was strongly stimulated by cimetidine. Heightening of the marginal mucosa resulted from active regeneration of the mucosal cells and made the endoscopic features mimic those of gastric cancer. These results suggest that it is necessary to differentiate clearly peptic ulcer from gastric cancer before beginning treatment of a gastric ulcer with cimetidine.