Alteration of H2 receptor sensitivity in duodenal ulcer patients after maintenance treatment with an H2 receptor antagonist.

The effects of a specific H2 receptor agonist impromidine, on gastric acid secretion were measured in six patients with duodenal ulcer in clinical remission before and after three months treatment with ranitidine 150 mg nocte. After treatment basal acid output increased from 1.2 to 2.8 mmol/h and after maximal impromidine stimulation from 36.9 (4.7) to 44.2 (6.2) mmol/h (p less than 0.02). Intravenous ranitidine 50 mg was given at the end of …