Treatment of bleeding gastric varices (GVs) is still controversial, mainly because of anecdotal studies or inclusion of patients with GVs located at different sites that have variable incidences of bleeding. A prospective study was undertaken to compare the efficacy and safety of GV sclerotherapy using alcohol and GV obturation using cyanoacrylate glue. Thirty-seven consecutive patients with portal hypertension and endoscopic evidence of isolated GVs, 17 presenting with histories of active bleeding, were randomized to receive endoscopic intervention either with alcohol (n = 17) or with cyanoacrylate glue (n = 20) injection. Variceal obliteration, rebleeding, or death was the endpoint. The glue was significantly more effective in achieving variceal obliteration than alcohol (100% vs 44%, p < 0.05). Furthermore, this could be achieved in a significantly shorter period (2.0 +/- 1.6 vs 4.7 +/- 3.2 wk, p < 0.05) and with a smaller volume of the agent. Cyanoacrylate glue injection could achieve arrest of acute GV bleeding more often than alcohol (89% vs 62%), and the need for rescue surgery was less; the difference was, however, not significant. Six patients died from uncontrolled GV bleeding, four being in the alcohol group. During a mean follow-up of 15.4 +/- 3.7 months there was no recurrence of GVs in either group. Our results show that cyanoacrylate is more effective and achieves GV obliteration faster than injection sclerotherapy with alcohol. It also appears to be more useful in controlling acute GV bleeding, with less of a need for rescue surgery.