The study comprises 31 patients with gastro-oesophageal reflux disease who received 8 weeks' treatment with ranitidine. Sixteen of the patients received in addition maintenance treatment with ranitidine (150 mg twice daily) for another 6 months, and fundoplication was performed on 15 patients. There was a significant improvement in endoscopic and histologic findings, a decrease in gastric acid secretion, and a reduction of symptoms during short-term treatment with ranitidine. No further improvement was seen in any of the factors after half a year of ranitidine. After surgery the total reflux time during 24 h decreased to practically zero, all patients had normal endoscopic findings and negative acid perfusion tests, and reflux symptoms had disappeared completely. Anti-reflux surgery was superior to treatment with ranitidine. Reflux oesophagitis is therefore not improved any further by a half year's treatment with ranitidine beyond what is achieved with short-term therapy.