Effects of cimetidine on stress ulcer and gastric acid secretion in the rat.

Cimetidine at 25, 50, and 100 mg/kg significantly inhibited gastric acid secretion in rats with chronic gastric cannulas. Rats receiving either 50 or 100 mg/kg of cimetidine secreted significantly less gastric acid 3 hr after injection. Cimetidine failed to reduce the number or size of gastric lesions in rats exposed to the activity-stress procedure, but cimetidine at 100 mg/kg significantly reduced the number and size of gastric lesions in rats subjected to a supine restraint procedure.