Non-steroidal anti-inflammatory drugs and gastrointestinal bleeding.

Non-steroidal anti-inflammatory drug use carries the risk of gastrointestinal complications (1% over 6 months) which is increased by a factor of 4 to 5, although strong differences are observed between different non-steroidal anti-inflammatory drugs. This risk is present in both the upper and lower gastrointestinal tract which indicates that non-steroidal anti-inflammatory drugs induces bleeding from both peptic ulcer and non-peptic ulcer sources. Symptoms are poor predictors of serious lesions and complications, which may occur without previous symptoms. At present, risk factors for non-steroidal anti-inflammatory drug-associated upper gastrointestinal bleeding are well defined and include ulcer or complication history, age, high non-steroidal anti-inflammatory drug dose, combination with corticosteroid and warfarin. Helicobacter pylori infection is not considered a risk factor for complications in non-steroidal anti-inflammatory drug users. There is a high prevalence of over-the-counter non-steroidal anti-inflammatory drug (especially aspirin) use among those presenting with gastrointestinal complications. Prophylactic aspirin regimens increase the risk of gastrointestinal bleeding. The potential beneficial effect of nitrate treatments (nitric oxide donors) in low dose aspirin users deserves further study. The mechanisms involved in the induction of gastrointestinal bleeding by non-steroidal anti-inflammatory drugs are poorly understood. Platelet activity inhibition associated with an abnormal, but reversible, prolongation of the bleeding time in susceptible individuals using aspirin might be a mechanism affecting no more than a third of patients with gastrointestinal bleeding.