Gastrointestinal bleeding is a common cause for presentation in the emergency room and hospitalization. The bleeding is usually categorized to upper or lower gastrointestinal bleeding. The purpose of this review article is to provide an overview of the incidence of gastrointestinal bleeding, etiology, risk factors, role of antithrombotics, evaluation of the severity of bleeding, therapy and outcome. Emphasis will be put on gastrointestinal bleeding within the Icelandic health care system but also in broader terms.

Table I . Causes of acute upper gastrointestinal bleeding

Table II . Causes of acute lower gastrointestinal bleeding

Table III. Patients with one point or less had 96% probability of not requiring hospital therapy