Endoscopic sclerotherapy is a procedure to treat bleeding esophageal varices and prevent future variceal bleeding. The procedure involves the passage of an esophagoscope and injection of a sclerosing agent into or around esophageal varices. The mechanisms by which injection sclerotherapy controls variceal hemorrhage are not understood completely but are thought to involve damage to the intima, intraluminal thrombosis, and intravascular fibrous organization.