Epidemiology of NSAID-related gastrointestinal side effects.

Finding the true incidence of gastrointestinal side effects due to non-steroidal anti-inflammatory drugs (NSAIDs) is extremely difficult. Included in every clinical trial is the spontaneous and NSAID-unrelated occurrence of gastrointestinal problems. On the basis of several different clinical studies (cohort, case control, case review, and double-blind studies) we feel that the following frequency estimate adequately describes the clinical situation: one-third of all patients using NSAIDs will experience gastrointestinal symptoms during a 3-month course of therapy. When specifically asked for, all kinds of unspecific gastrointestinal symptoms will be encountered, ranging from vague complaints about intestinal distension to typical duodenal ulcer symptoms. In approximately half of the symptomatic patients these symptoms can be classified as dyspeptic. Serious gastrointestinal hemorrhage or perforation can be expected in 1%, and less than half of these patients will have experienced dyspeptic symptoms before the serious incident. More than 10% of all patients will withdraw from the planned treatment owing to intolerable symptoms.