Objective: The herbal preparation Iberogast has been reported to improve upper abdominal symptoms in functional dyspepsia (FD) and to decrease fundic tone, increase antral contractility, and decrease afferent nerve sensitivity in experimental animals. The effects of Iberogast on the human gastrointestinal tract have not been evaluated.
Methods: We investigated the effects of oral control and Iberogast, each administered as a single dose (1.1 mL), in a double-blind randomized fashion, on proximal gastric volume (part A), antropyloroduodenal motility (part B), and gastric emptying and intragastric distribution of a solid/liquid meal (part C) for 120 minutes, in nine (part A), 12 (part B), and eight (part C) healthy men.
Results: Iberogast increased proximal gastric volume (max volume; control 104+/-12 mL, Iberogast 174+/-23 mL, P<0.05) (part A), increased the motility index of antral pressure waves in the first 60 minutes (P<0.05) without affecting pyloric or duodenal pressures (part B), and slightly increased the retention of liquid in the total stomach between 10 and 50 minutes (P<0.01), but had no effect on gastric emptying of solids or intragastric distribution (part C).
Conclusions: Iberogast affects gastric motility in humans, probably in a region-dependent manner. The stimulation of gastric relaxation and antral motility may contribute to the reported therapeutic efficacy of Iberogast in FD.