Effects of the herbal preparation STW 5‐II on in vitro muscle activity in the guinea pig stomach

Abstract

Background STW 5 is a combination of nine medicinal herbal extracts and used to treat functional gastrointestinal disorders including functional dyspepsia. It has a region‐specific effect by relaxing the proximal and contracting the distal stomach. The research combination STW 5‐II (Iberogast® Advance) lacks three herbal extracts but seems clinically as effective as STW 5. However, the action of STW 5‐II on gastric motility is unknown. Methods In vitro circular and longitudinal muscle tone and contractility were recorded from guinea pig gastric fundus and antrum with isometric force transducers. Key Results STW 5‐II decreased concentration‐dependently (64‐512 µg/ml) the tone of circular and longitudinal muscle strips from the fundus. In contrast, STW 5‐II increased concentration‐dependently contraction amplitude in antral circular and longitudinal muscle. The effects were region‐dependent but comparable in the two muscle layers. Application of 512 µg STW 5 or STW 5‐II revealed comparable effects in the fundus and antrum circular and longitudinal muscle strips. Conclusions and Interferences STW 5‐II had a region‐specific effect and relaxed the proximal stomach but increased the contractility in the antrum. It was as effective as STW 5 which may explain its comparable clinical effects in treating functional dyspepsia. Impaired accommodation may be normalized through relaxation of the fundus, while the motility‐promoting effects leading to an increase in antral motility may activate the gastric pump.

The Effect of STW5 (Iberogast) on Reflux Symptoms in Patients With Concurrent Dyspeptic Symptoms: A Double-blind Randomized Placebo-controlled Crossover Trial

“…Previous in vitro studies have shown that STW5 has a region-specific effect on gastric motility by relaxing the proximal stomach and increasing antrum contractility. 8,18,19 This region-specific effect was also described by Pilichiewicz et al, 7 who studied 29 healthy volunteers and found that STW5 increased proximal gastric volume while increasing antral pressure waves. These findings may suggest a mechanistic rationale for STW5.…”

Double‐blind, randomized, 8‐week multicenter study of the efficacy and safety of STW 5‐IIversus placebo in functional dyspepsia

“…A mechanistic explanation of the efficacy of STW 5‐II in relieving postprandial distress symptoms may be its effect on sensory afferent neuronal signaling from the GI tract to the central nervous system, reducing stimuli for visceral hypersensitivity 35 . Furthermore, region‐specific effects of relaxing the proximal stomach and increasing contractility in the antrum have been described for STW 5‐II, 14 offering another possible mechanistic explanation for the short‐term efficacy of STW 5‐II. The broad anti‐inflammatory effects 12,15–17 described for STW 5‐II could explain the clinical efficacy seen over the 8‐week period, potentially acting against the low‐grade duodenal and gastric inflammation that have been posited as a potential mechanism underlying FD 36–38 …”

“…STW 5‐II contains only six herbal extracts ( Iberis amara , Carum carvi , Glycyrrhiza glabra , Matricaria chamomilla , Melissa officinalis , and Mentha piperita ). In pharmacological studies, STW 5‐II and its herbal components have shown a broad spectrum of mechanistic actions, including anti‐inflammatory effects, mucosal protection, and modulation of upper GI tract motility 12–17 . Placebo‐ and active‐controlled clinical studies in FD patients have yielded clinical evidence for the efficacy of STW 5‐II.…”

“…In pharmacological studies, STW 5‐II and its herbal components have shown a broad spectrum of mechanistic actions, including anti‐inflammatory effects, mucosal protection, and modulation of upper GI tract motility. 12 , 13 , 14 , 15 , 16 , 17 Placebo‐ and active‐controlled clinical studies in FD patients have yielded clinical evidence for the efficacy of STW 5‐II. Two of these studies addressed efficacy up to 4 weeks.…”

Efficacy and Safety of STW 5-II for Functional Dyspepsia Treatment: A Patient Data-Based Meta-Analysis

“…Pharmacological studies have demonstrated that STW 5-II affects multiple targets, explaining its clinically proven efficacy in relieving FD-related symptoms [10][11][12][13]. One investigation showed that STW 5-II has a dual mode of action on gastric motility, i.e., by relaxing the gastric fundus and corpus and toning the antrum [14]. Additional mechanisms of action include the desensitization of hypersensitive afferents [15] and broad anti-inflammatory effects through normalizing histological parameters of inflammation [16] and reducing the levels of several proinflammatory chemokines [17][18][19].…”