Retrospective analyses of two multicentre clinical trials were carried out to examine the association of age with endoscopically verified reflux oesophagitis lesions and symptoms before and after 4 or, if necessary, 8 weeks randomized double-blind treatment with omeprazole (20 mg o.m.) or histamine H2-receptor antagonists (H2RA) (cimetidine 400 mg q.d.s. or ranitidine 150 mg b.d.). Of the elderly patients (> or = 65 years) 79 received omeprazole, 39 cimetidine and 36 ranitidine; of the young patients (< 65 years) 200 received omeprazole, 94 cimetidine and 102 ranitidine. The objective of treatment was to heal the oesophagus and to relieve the patient's symptoms. On completion of the studies the proportion of elderly omeprazole-treated patients (68%) healed and symptom-free was nearly three times that of elderly H2RA-treated patients (23%, p < 0.001). In the young patient group the proportion of omeprazole-treated patients (57%) both healed and symptom-free was nearly twice that of H2RA-treated patients (29%, p < 0.001). The advantage of omeprazole over H2RA, in terms of endoscopic healing and symptom relief, is at least as great in elderly patients as in younger patients.