Product Review

Functional Gastrointestinal Relief Possible

Two functional gastrointestinal conditions, perhaps related, are functional dyspepsia (FD) and irritable bowel syndrome (IBS). Many patients with either of these conditions also experience symptoms of the other condition. For example, in one survey of patients with IBS, 87% developed symptoms of dyspepsia,1 and in another, more than 50% of dyspeptic patients developed symptoms of IBS over a 5-7 year period.2

These conditions are similar in that symptoms are typically chronic in nature, may wax and wane, and may worsen following meals. Characteristically, these complaints are sporadic, poorly localized, and without consistent identifiable aggravating or relieving factors. Psychosocial stressors play a role in both ailments. In addition, diagnosing these disorders may be challenging and take some time; a detailed history is central to the diagnosis, and extensive testing is unlikely to be helpful except to rule out other disorders. The similarities between IBS and FD raise the issue as to whether they are just different manifestations of the same disorder or whether they represent distinct clinical entities.3 My personal view is that they represent different points along a continuous spectrum that may generally termed functional gastrointestinal disorders.

Functional Dyspepsia (FD)

FD, previously known as non-ulcer dyspepsia, is a sensory and motility problem of the digestive tract, where sensation and peristalsis – the normal downward pumping and squeezing of the esophagus, stomach, and duodenum – are disturbed. This leads to what is sometimes called visceral hyperalgesia, or amplified sensation, especially of unpleasant feelings; and impaired distensibility or uncoordinated and even ineffectual emptying of the upper gut, with resulting symptoms of pain, fullness, and bloating and inability to finish full meals. Around 20-29% of Canadians have FD but only a small number will consult a doctor.

Irritable Bowel Syndrome (IBS)

IBS affects approximately 20% of the Canadian population. Symptoms include abdominal pain, bloating and gas, constipation and/or diarrhea, sometimes alternating between the two stool consistencies. Defecation usually temporarily relieves the abdominal discomfort. At present, many gastroenterologists classify IBS as a distinctly separate functional bowel disorder from dyspepsia. However, upper gastrointestinal (GI) function regularly affects lower GI tract function, and vice versa.4 A recent study found delayed gastric emptying in patients with overlapping IBS and FD symptoms, whereas patients with IBS alone had emptying rates similar to those of healthy controls.5


The prime goal of therapy for functional GI conditions is to alleviate the patient’s pain and discomfort and then to relieve secondary symptoms including bloating and upper abdominal fullness in patients with dyspepsia; and constipation, bloating, diarrhea, and urgency in patients with IBS. Education helps patients understand why their symptoms are occurring. Patients also benefit from reassurance that pathology that is more serious has been ruled out.

For more information on treating dyspepsia and IBS with dietary and lifestyle modifications and/or medications, please contact the CSIR office. This article is focusing on a phytopharmaceutical (plant medicine) consisting of plant extracts used to treat both the upper and lower GI conditions of functional dyspepsia and IBS, called Iberogast® (STW 5).


Made in Germany and used throughout Europe and other parts of the world for more than forty years, Iberogast came to Canada in 2006. Of the estimated 20,000,000 patients using Iberogast, only 18 reported adverse events over the years.

Dyspepsia and IBS often have multiple underlying functional causes and this product, containing nine active ingredients, affects various functional mechanisms to alleviate several underlying factors in a complimentary, synergistic way.6,7 It contains no sugar, salt, yeast, wheat, gluten, corn, soy, dairy products, artificial colouring, artificial flavouring, or preservatives. It contains a small amount of alcohol. The components in this product, shown across the bottom of these pages, work together facilitating a number of digestive improvements such as:

  • Regulation of peristalsis – by relieving or preventing intestinal spasms and by strengthening, coordinating, and toning the smooth muscles within the digestive tract.8 This happens when the stomach’s upper area relaxes while the lower area, where the food passes to the intestines, is toned.9
  • Reduces acid production and improves digestive secretions, by positively affecting the mucous membranes of the stomach and the intestines.8 When the product interacts with the bitter receptors in the taste buds on the tongue, this stimulates digestive secretions.
  • Carminative – this means that the product helps induces the expulsion of gas from the stomach and intestines.8 It also helps reduce gas formation.
  • Local anaesthetic – the product elicits mild pain relief by numbing some areas within the digestive tract.8 Patients with functional GI ailments often have an increased sensitivity to pain. It is difficult to know how much of this effect is truly due to reducing the sensitivity of nerve endings, since most of the pain receptors in the gut are within the nerve plexuses in the muscle layers, and not in the mucosa, or inner lining layer.
  • Free radical scavenging properties of this product help with possible digestive inflammation cascades from certain foods, which release free radicals in the gastrointestinal tract triggering inflammation and related dyspepsia.
  • Antibacterial – the constituent components of STW 5 inhibit the growth of six subspecies of Helicobacter pylori, a bacterium that frequently infects the stomach. However, the role of Helicobacter pylori in causing FD is probably minimal if anything, in most patients.
  • Dyspepsia-specific Research A recent study found that FD patients taking Iberogast had significantly reduced gastrointestinal symptoms compared to the control group who were taking placebo. Of patients taking Iberogast, 86% reported a therapeutic effect after four weeks of treatment.10 Results from a meta-analysis, which combined data from multiple, varied, small trials performed over the past decade, reinforce these findings of significantly more effectiveness than placebo in providing symptomatic relief to patients with FD. This seems even more evident with associated symptoms of gastroesophageal reflux (GERD) or predominance of upper GI pain. The researchers compiling the data agreed that although the cumulative total of patients in this meta-analysis was relatively limited, it was still large enough to demonstrate efficacy, even though they suggest more research.11 Another trial showed statistically equivalent efficacy in treating gastrointestinal symptoms to the now unavailable prokinetic (motility stimulant) agent, cisapride (Prepulsid®).12
  • IBS-specific Research A four-week study involving 208 patients with IBS in 2004 showed Iberogast as significantly better than placebo in reducing both the total abdominal pain score and IBS symptom score. On average, patients found Iberogast to treat some symptoms 20% better than placebo, and the proportion of patients with complete relief was more than 50% greater than placebo.13 By acting on two different serotonin receptors in the gut, positive results with Iberogast were for patients who had predominant symptoms of diarrhea, constipation, and altering stool consistencies.14


Even though Iberogast derives from plants, with its efficacy in the area of functional gastrointestinal ailments, clinically confirmed by long-term traditional use and pharmacological investigations, it belongs with the evidence-based pharmaceutical products. It is worth a try if you have non-ulcer dyspepsia or irritable bowel syndrome. You just might find relief.

First published in the Inside Tract® newsletter issue 163 – September/October 2007
Note: The GI Society has received no remuneration from Iberogast® or its affiliates for this review.
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2. Sloth H, et al. Predictors for the course of chronic non-organic upper abdominal pain. Scandinavian Journal of Gastroenterology. 1989;24:440-444.
3. Noddin L, et al. Irritable Bowel Syndrome and Functional Dyspepsia: Different Diseases or a Single Disorder With Different Manifestations? Medscape General Medicine. 2005;7(3):17.
4. Tjeerdsma HC, et al. Voluntary suppression of defecation delays gastric emptying. Digestive Diseases and Sciences. 1993;38:832-836.
5. Stanghellini V, et al. Dyspeptic symptoms and gastric emptying in the irritable bowel syndrome. American Journal of Gastroenterology. 2002;97:2738-2743.
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12. Rösch W, et al. A Randomized Clinical Trial Comparing the Efficacy of a Herbal Preparation STW 5 with the Prokinetic Drug Cisapride in Patients with Dysmotility Type of Functional Dyspepsia. Zeitschrift für Gastroenterologie. 2002;40:401-408.
13. Madisch A, et al. Treatment of irritable bowel syndrome with herbal preparations: results of a double-blind, randomized, placebo-controlled, multi-centre trial. Alimentary Pharmacology & Therapeutics. 2004;19: 271-279.
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