The aim of this study was to determine appropriate endoscopic treatment of patients with bleeding ulcers by synthesizing results of randomized controlled trials. We performed dual independent bibliographic database searches to identify randomized trials of thermal therapy, injection therapy, or clips for bleeding ulcers with active bleeding, visible vessels, or clots, focusing on results from studies without second-look endoscopy and re-treatment. The primary end point was further (persistent plus recurrent) bleeding. Compared with epinephrine, further bleeding was reduced significantly by other monotherapies (relative risk [RR], 0.58 [95% CI, 0.36-0.93]; number-needed-to-treat [NNT], 9 [95% CI, 5-53]), and epinephrine followed by another modality (RR, 0.34 [95% CI, 0.23-0.50]; NNT, 5 [95% CI, 5-7]); epinephrine was not significantly less effective in studies with second-look and re-treatment. Compared with no endoscopic therapy, further bleeding was reduced by thermal contact (heater probe, bipolar electrocoagulation) (RR, 0.44 [95% CI, 0.36-0.54]; NNT, 4 [95% CI, 3-5]) and sclerosant therapy (RR, 0.56 [95% CI, 0.38-0.83]; NNT, 5 [95% CI, 4-13]). Clips were more effective than epinephrine (RR, 0.22 [95% CI, 0.09-0.55]; NNT, 5 [95% CI, 4-9]), but not different than other therapies, although the latter studies were heterogeneous, showing better and worse results for clips. Endoscopic therapy was effective for active bleeding (RR, 0.29 [95% CI, 0.20-0.43]; NNT, 2 [95% CI, 2-2]) and a nonbleeding visible vessel (RR, 0.49; [95% CI, 0.40-0.59]; NNT, 5 [95% CI, 4-6]), but not for a clot. Bolus followed by continuous-infusion proton pump inhibitor after endoscopic therapy significantly improved outcome compared with placebo/no therapy (RR, 0.40 [95% CI, 0.28-0.59]; NNT, 12 [95% CI, 10-18]), but not compared with histamine(2)-receptor antagonists. Thermal devices, sclerosants, clips, and thrombin/fibrin glue appear to be effective endoscopic hemostatic therapies. Epinephrine should not be used alone. Endoscopic therapy should be performed for ulcers with active bleeding and nonbleeding visible vessels, but efficacy is uncertain for clots. Bolus followed by continuous-infusion intravenous proton pump inhibitor should be used after endoscopic therapy.