Gastric variceal hemorrhage is associated with a high morbidity and mortality. We report the efficacy and safety of bovine thrombin in the treatment of bleeding gastric varices. At endoscopy 52 patients with hematemesis were diagnosed with bleeding gastric varices. Patients were treated by intravariceal injection with bovine thrombin and underwent further endoscopy at 72 hr and then at two-week intervals. Initial hemostasis was achieved in 49/52 patients (94%). Bleeding-related mortality at 72 hr after the index bleed was 3/52 (6%). The mean amount of thrombin used to achieve initial hemostasis was 1070 IU (range 400-2000 IU) and no adverse drug effects were observed. The median number of treatment sessions required to achieve gastric variceal ablation was 2 (range 1-3). At six weeks, 9 of 49 surviving patients (18%) rebled and one further patient died. The six-week mortality in patients treated with thrombin was 4/52 (8%). In conclusion, safe and effective hemostasis of bleeding gastric varices can be achieved by intravariceal injection with thrombin.