E0 ConsensusPreliminaryPEM unclearSystematic-ReviewPeer-reviewedMachine draft
Efficacy and safety of Xiaoyao San in the treatment of chronic fatigue syndrome: a systematic review and meta-analysis.
Wang, Qianqian, Zhou, Jian, Gong, Guanwen · Frontiers in pharmacology · 2025 · DOI
Quick Summary
This review looked at whether Xiaoyao San, a traditional Chinese herbal treatment, helps people with chronic fatigue syndrome (ME/CFS). Researchers examined 6 studies with 623 patients and found that Xiaoyao San improved fatigue, reduced anxiety and depression, and caused fewer side effects compared to standard treatments. However, the overall quality of evidence was low, so we need larger, better-designed studies to be confident about these results.
Why It Matters
This review synthesizes emerging evidence on a widely-used herbal treatment for ME/CFS in clinical practice, particularly in China. For patients exploring complementary approaches and for clinicians seeking evidence-based guidance, this meta-analysis provides an initial systematic assessment of XYS efficacy and safety profiles.
Observed Findings
- XYS improved effective rate by 27% compared to standard biomedical treatment (RR=1.27, 95% CI: 1.18-1.37).
- FS-14 fatigue scores improved by 1.77 points with XYS-based interventions (95% CI: 1.49-2.06).
- When combined with standard treatment, XYS reduced anxiety scores by 5.16 points (SAS; 95% CI: 3.84-6.48).
- When combined with standard treatment, XYS reduced depression scores by 4.62 points (SDS; 95% CI: 3.15-6.09).
- Adverse event risk was 52% lower in the XYS+SBT group compared to SBT alone (RR=0.48, 95% CI: 0.32-0.72).
Inferred Conclusions
- Xiaoyao San appears effective and safe for improving fatigue, anxiety, and depression in CFS patients, both alone and in combination with standard treatments.
- Combining XYS with standard biomedical treatment may confer additional benefits and lower adverse event risk compared to standard treatment alone.
- The current evidence base is insufficient to make strong clinical recommendations due to low quality ratings and methodological limitations.
Remaining Questions
- What are the active components of XYS responsible for its apparent efficacy, and what are the underlying biological mechanisms?
- How do different formulations and dosing regimens of XYS compare in efficacy and safety?
What This Study Does Not Prove
This review does not establish causation or validate the biological mechanisms by which XYS might work; it only demonstrates association in controlled trials. The low quality of underlying evidence means results should be interpreted cautiously and cannot yet inform definitive clinical recommendations. Additionally, the findings may not generalize to populations outside the studied regions or to different XYS formulations.
Tags
Symptom:Cognitive DysfunctionFatigue
Method Flag:Weak Case DefinitionSmall Sample
Metadata
- DOI
- 10.3389/fphar.2025.1496774
- PMID
- 39981187
- Review status
- Machine draft
- Evidence level
- Established evidence from major reviews, guidelines, or evidence maps
- Last updated
- 8 April 2026
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
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