Dyspepsia is a catchall term that includes a variety of digestive problems such as stomach discomfort, gas, bloating, belching, appetite loss, and nausea. Although many serious medical conditions can cause similar symptoms, the term dyspepsia is used in those cases when no other identifiable medical cause can be determined.

Because dyspepsia has, by definition, no known medical cause, there is no apparent way to develop medical treatments to address it. Many people with dyspepsia simply experiment with medications, as well as remove foods from their diet. However, substantial double-blind, placebo-controlled studies suggest that a proprietary herbal combination may provide benefit. Sold under the tradename Iberogast, this preparation consists primarily of candytuft, along with chamomile, peppermint leaves, caraway, licorice root, lemon balm, angelica root, celandine, and milk thistle.

A double-blind study published in May 2007 enrolled a total of 315 people with dyspepsia. Researchers evaluated the severity of the condition through the use of a standardized questionnaire, the Gastrointestinal Symptom Score (GIS) scale. Participants received either placebo or Iberogast at a dose of 20 drops three times daily. Over the eight-week study period, participants given Iberogast showed significantly greater improvement in GIS scores than those given placebo.

Several earlier double-blind studies, enrolling a total of about 300 people, had also shown benefit. However, many of these used an earlier version of Iberogast that lacked some of the herbs used in the current product.

For more information, see the full dyspepsia and candytuft articles.