Bleeding from esophageal varices is a severe complication of portal hypertension. After initial control of acute variceal bleeding, patients have up to a 70% risk of rebleeding. Of those do rebleed, there is a 20%-35% mortality rate. Therefore, preventive procedures are required for patients surviving an episode of acute variceal bleeding. Both endoscopic injection sclerotherapy (EIS) and propranolol have been well documented to be effective for the prevention of variceal rebleeding. In recent years, endoscopic variceal ligation (EVL) has replaced EIS as the endoscopic treatment of choice in the management of bleeding esophageal varices. On the other hand, the addition of isosorbide-5-mononitrate (ISMN) has been shown to be even more effective than propranolol alone in the reduction of portal pressure and in the prevention of variceal rebleeding. A controlled trial showed that the combination of nadolol and ISMN was better than EIS in terms of prevention of variceal rebleeding and complications. The combination of nadolol and ISMN has been shown to be better than EVL in preventing variceal rebleeding. However, our study showed a contradictory result. On the other hand, carvedilol is shown to be superior to propranolol to reduce the portal pressure. This study was undertaken to compare the effectiveness and complication rates of nadolol and ISMN with carvedilol in the prevention of rebleeding from esophageal varices.