Analgesics and the stomach.

A review of the literature on the gastrointestinal side effects of the analgesic drugs has disclosed a disparity between generally held views and the scientific evidence. This is largely due to the paucity of large long term controlled trials since the cost of these is very high. The problems in mounting a large observational study with population controls are discussed against a backgrwound of exploratory work in Australia and New Zealand and the conclusion is reached that a comprehensive survey is needed. The difficulties in mounting such a survey are discussed.