Systematic review: herbal medicinal products for non-ulcer dyspepsia.

BACKGROUND Non-ulcer dyspepsia is predominantly a self-managed condition, although it accounts for a significant number of general practitioner consultations and hospital referrals. Herbal medicinal products are often used for the relief of dyspeptic symptoms. AIMS : To critically assess the evidence for and against herbal medicinal products for the treatment of non-ulcer dyspepsia. METHODS Systematic searches were performed in six electronic databases and the reference lists located were checked for further relevant publications. No language restrictions were imposed. Experts in the field and manufacturers of identified herbal extracts were also contacted. All randomized clinical trials of herbal medicinal products administered as supplements to human subjects were included. RESULTS Seventeen randomized clinical trials were identified, nine of which involved peppermint and caraway as constituents of combination preparations. Symptoms were reduced by all treatments (60-95% of patients reported improvements in symptoms). The mechanism of any anti-dyspeptic action is difficult to define, as the causes of non-ulcer dyspepsia are unclear. There appear to be few adverse effects associated with these remedies, although, in many cases, comprehensive safety data were not available. CONCLUSIONS There are several herbal medicinal products with anti-dyspeptic activity and encouraging safety profiles. Further research is warranted to establish their therapeutic value in the treatment of non-ulcer dyspepsia.