STW 5-II for Treatment of Functional Gastrointestinal Disorders: Mechanism and Clinical Efficacy

Dig Dis. 2025;43(3):266-272. doi: 10.1159/000544695. Epub 2025 Feb 20.

Abstract

Background: Functional dyspepsia (FD) is currently defined as episodic or recurrent epigastric pain or discomfort in the absence of organic diseases, lasting at least 4 weeks. FD is estimated to affect 7.2% of the worldwide population. Due to the underlying complex pathogenetic mechanisms, the therapy for FD is generally prescribed to treat the main symptoms experienced by the patient.

Summary: Recently, a new herbal formulation has been proposed for treating FD. This plant-based preparation, called STW 5-II, is a fixed combination of six hydroethanolic herbal extracts from bitter candy tuft, peppermint leaf, chamomile flower, licorice root, caraway fruit, and melissa leaf. STW 5-II has been shown to be more effective than placebo in several controlled studies and clinical scenarios, allowing for its recent introduction into several European markets.

Key messages: This review aimed to describe the mechanisms of action of this herbal drug, its current and potential clinical indications, and to explore future perspectives for its use.

Keywords: Functional dyspepsia; Gastroesophageal reflux disease; Herbal drug; Irritable bowel syndrome; Treatment.

Publication types

  • Review

MeSH terms

  • Dyspepsia* / drug therapy
  • Gastrointestinal Diseases* / drug therapy
  • Humans
  • Phytotherapy* / methods
  • Plant Extracts* / pharmacology
  • Plant Extracts* / therapeutic use
  • Treatment Outcome

Substances

  • Plant Extracts