Incidence of gastrointestinal bleeding in most populations is about 1 per 1,000 inhabitants. More than 65% of all bleeding episodes are associated with drug use. The most often involved are non-steroidal antiinflammatory drugs and low doses of acetyl-salicylic acid. The mortality within the first month after the bleeding episode is about 10–12%, and has not significantly changed in the last decade. Therefore, bleeding prevention is of major importance. Appropriate selection of patients, proper drug choice, application of lowest efficient doses of potentially ulcerogenic drugs, and use of drugs that inhibit gastric acid secretion remain cornerstone preventive measures of gastrointestinal bleeding.