Effect of treatment with cimetidine for one year on gastrin cell and parietal cell function and sensitivity to cimetidine in patients with duodenal or gastric ulcers.

Twenty-two duodenal and 16 gastric ulcer patients were treated with 400 mg cimetidine twice daily for one year after their ulcers had healed. No change in gastric acid secretion was observed before and after treatment in 20 duodenal and 13 gastric ulcer patients. Similarly, the inhibitory effect of 200 mg cimetidine on gastric acid secretion was unaltered in 11 duodenal and 6 gastric ulcer patients studied and cimetidine blood concentration were unchanged in 9 duodenal and 4 gastric ulcer patients after one year. In 7 duodenal and 6 gastric ulcer patients the serum gastrin response to a standard test meal before and after treatment was identical.