Cimetidine reduces the risk of rebleeding from duodenal ulcers displaying signs of recent haemorrhage.

The presence of endoscopic signs of recent haemorrhage (SRH) greatly increases the risk of rebleeding from peptic ulcers. Fifty-five patients with acute bleeding from chronic duodenal ulcers with SRH completed a randomized double-blind trial to assess the effect of administration of cimetidine (800 mg daily intravenously for 2 days, then 1000 mg daily orally for 10 days in divided doses) versus placebo on rebleeding and need for emergency surgery. In the cimetidine group (n = 29), 5 rebled, compared with 11 receiving placebo (n = 26) (p less than 0.05; relative risk, 0.28, 95% confidence interval, 0.08-0.97). This reduction in rebleeding rate in the cimetidine-treated patients was observed only in subjects over 60 years of age. Fifteen patients receiving cimetidine required blood transfusion (mean, 2.3 +/- 0.6 (SEM) units per patient) compared with 19 receiving placebo (3.5 +/- 0.5) (p greater than 0.1). Emergency surgery to arrest bleeding was required in three patients receiving cimetidine and four receiving placebo (p greater than 0.5). Cimetidine therapy should be considered in patients more than 60 years old who present with haemorrhage from a chronic duodenal ulcer with SRH and who are at high risk of rebleeding.