It has common knowledge that the advent of H2-blockers has radically changed the treatment of peptic ulcer. We reviewed 26,667 endoscopic examinations, 5,800 consecutive autopsies and 134 consecutive patients operated for peptic ulcer over an 18-year period to evaluate the effects of H2-blockers on the treatment of peptic ulcer in the elderly (> or = 60 years of age). The number of operations for peptic ulcer in the elderly markedly declined after H2-blocker therapy was introduced. This is mainly due to decreased operative indications for gastric bleeding as a result of conservative treatment. However, the incidence of perforating ulcers has hardly changed even after the introduction of H2-blockers. More than 90% of these cases were non-diagnosed or non-treated ulcers and 50% of them were NSAID- or steroid-treated, which is characteristic in the elderly. We conclude that patients to be treated by anti-inflammatory drugs should be screened by endoscopy, and should be given anti-ulcer drugs prophylactically if necessary.