Assessing the safety of drugs for the long-term treatment of peptic ulcers.

Two clinical features of ulcer disease (and related, or associated, diseases such as oesophagitis) are of cardinal importance in determining the nature of anti-ulcer therapy -the tendency of the disease to relapse and the likelihood that repeated relapses will occur for many years: perhaps throughout the lifetime of many patients. At some time during the life of patients with an ulcer, relapse results in haemorrhage in one-third of affected individuals2 and in perforation in about 10%3 so that any relapse is potentially lethal. The aim of the treatment of ulcer disease must therefore be to prevent relapse.