CHRISTIANSEN, P. M. & R~D B R O , P. Gastric Secretory Patterns before and during Treatment with 1-Hyoscyamine. Scand. J. Gusfroent. 2, 251-256, 1967.Ten male patients with chronic duodenal ulceration were examined with an augmented histamine test before and during treatment with optimal effective doses of long acting 1-hyoscyamine. The outputs and secretory patterns for volume, acid, pepsin, and intrinsic factor were determined. The basal and stimulated secretion of volume and acid were significantly reduced during treatment, while the pepsin and intrinsic factor secretion were virtually unaltered. The results of acid secretion were compared to those after effective surgical vagotomy. The reduction in acid output after vagotomy was in all patients except one more pronounced than during treatment with I-hyoscyamine.