Action of mifentidine on the secretory response to sham feeding and pentagastrin and on serum gastrin in duodenal ulcer patients.

A study has been done in 10 duodenal ulcer patients of the effect of a single oral dose of 10 mg mifentidine on the acid and pepsin responses to sham feeding after 1 h 30 min and to pentagastrin after 4 h 15 min. The study followed a double-blind, randomized, placebo-controlled, cross-over design. Gastric juice was collected for 5 h 15 min after treatment. Blood was sampled for up to 3 h 30 min to determine the effects of mifentidine on serum gastrin. Mifentidine suppressed basal acid output by 77% and sham feeding-stimulated acid output by 71% vs the placebo values. Pentagastrin-stimulated acid output was inhibited by 30% throughout the pentagastrin infusion. The suppressant effect of the drug on pepsin output was not as marked as on acid secretion. Mifentidine did not affect the serum gastrin level during the basal and sham feeding phases. No untoward effects were reported by the patients. The results show that 10 mg mifentidine p.o. produced a large reduction in the acid output in response to sham feeding and pentagastrin without affecting the serum gastrin responses.