Iberogast in functional dyspepsia: yesterday, today, and tomorrow - a narrative review of a multitarget phytomedicine

Introduction: Functional dyspepsia (FD) is a highly prevalent disorder of gut–brain interaction, characterized by heterogeneous symptoms, overlapping pathophysiology, and limited treatment efficacy. Iberogast®, a multi-herbal phytomedicine available for more than five decades, has emerged as a promising therapeutic option by addressing multiple mechanisms simultaneously. Areas covered: This narrative review summarizes the pharmacological rationale, mechanisms of action, and clinical evidence supporting Iberogast’s role in FD and related conditions. Literature was identified through searches of PubMed, Scopus, and Web of Science, complemented by reference screening, with the last update on 19 August 2025. Particular attention is given to the original nine-component formulation (STW 5) and the refined six-component version (STW 5-II). Evidence from randomized controlled trials, meta-analyses, mechanistic studies, and real-world data is synthesized to provide an integrated appraisal of efficacy, safety, and therapeutic positioning. Expert opinion: Iberogast remains an evidence-based phytomedicine with a favorable safety profile, filling therapeutic gaps in FD by targeting motility, hypersensitivity, inflammation, and barrier function. Future research should include trials comparing Iberogast with established drugs, evaluating cyclic therapy in real-world settings, and exploring new indications such as irritable bowel syndrome, inflammatory bowel disease, use in pediatrics, and overlapping dyspepsia–reflux phenotypes.