Total 24-hour gastric acid secretion in patients with duodenal ulcer. Comparison with normal subjects and effects of cimetidine and parietal cell vagotomy.

The purposes of these studies were as follows: (a) to compare gastric acid secretion throughout an entire 24-h period in 8 patients with duodenal ulcer disease and in 7 normal subjects, and (b) to determine in duodenal ulcer patients to what extent total, 24-h acid secretion was reduced by oral cimetidine (n = 7) or parietal cell vagotomy (n = 7). Basal, interprandial, and nocturnal acid secretion were measured by gastric aspiration, whereas acid secretion in response to breakfast, lunch, and dinner was measured by in vivo intragastric titration. Total, 24-h acid secretion averaged 408.3 +/- 61.7 mmol in duodenal ulcer patients and 208.3 +/- 18.5 mmol in normal subjects (p less than 0.02). Acid secretion was higher in duodenal ulcer patients than in normal subjects during both day (p less than 0.01) and night (p less than 0.05). Cimetidine (400 mg twice daily) significantly (p less than 0.001) reduced total, 24-h acid secretion in duodenal ulcer patients to 235.3 +/- 58.6 mmol, a rate that was not significantly different from 24-h acid secretion in normal subjects. On the other hand, total, 24-h acid secretion averaged only 86.7 +/- 20.7 mmol after parietal cell vagotomy, a rate that was significantly lower than 24-h acid secretion in normal subjects (p less than 0.001) and in duodenal ulcer patients receiving cimetidine (p less than 0.05). These studies indicate that patients with duodenal ulcer disease secrete excessive amounts of gastric acid during the day and night and throughout an entire 24-h period. A twice-daily 400-mg dose of cimetidine reduces 24-h acid secretion in duodenal ulcer patients to nearly normal rates, whereas parietal cell vagotomy reduces acid secretion to well below normal rates.