The Effects of STW 5-II on Duodenal Mucosa and Symptoms in Functional Dyspepsia

The goal of this clinical trial is to find out whether a herbal medicine called STW 5-II can help improve gut health and symptoms in adults recently diagnosed with functional dyspepsia (FD)-a condition that causes frequent stomach discomfort, especially after eating. The main questions it aims to answer are: Can STW 5-II reduce certain immune cells (eosinophils) in the gut lining? Can it improve symptoms like severe postprandial fullness, bloating, epigastric pain, and improve quality of life? Researchers will compare STW 5-II to a placebo to see if it helps reduce gut inflammation and ease symptoms. Participants will: Take either STW 5-II or a placebo for 8 weeks Provide small samples of gut tissue (via endoscopy) Answer questions about their symptoms and daily life An optional 4-week treatment with STW 5-II will follow for all participants.