Endoscopic treatment of bleeding peptic ulcers is effective to prevent rebleeding. Adjuvant medical treatment to increase gastric pH may further decrease rebleeding. Recent studies on potent acid suppression by proton pump inhibitors (PPI) demonstrated the efficacy in preventing rebleeding. Lau demonstrated that high dose intravenous infusion of omeprazole decreased rebleeding in peptic ulcers with stigmata of recent hemorrhage.