Background: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder worldwide, characterized by recurrent abdominal pain and altered bowel habits, which significantly impair quality of life and impose a socioeconomic burden. Traditional pharmacological treatments have limited efficacy and are often associated with side effects, highlighting the need for effective non-pharmacological interventions. Non-invasive transcutaneous nerve stimulation (NITNS) has shown potential in improving IBS symptoms and autonomic function, but systematic evidence is lacking. Objectives: To systematically evaluate the efficacy and safety of NITNS in IBS and explore its potential mechanisms. Design: Systematic review and meta-analysis. Data sources and methods: Randomized controlled trials (RCTs) were identified through PubMed , Embase , Cochrane Library , and Web of Science from database inception to September 28, 2025. Studies included patients aged 18–75 years who met IBS diagnostic criteria. Interventions involved NITNS, with sham-NITNS as the control. Primary outcomes were IBS symptom severity scale (IBS-SSS) and IBS quality of life (IBS-QOL). Secondary outcomes included visual analogue scale (VAS), Bristol stool form scale (BSFS), heart rate variability (HRV), and adverse events (AEs). Data extraction and risk-of-bias assessment were independently performed by two reviewers. Results: Four RCTs, including 170 patients, were analyzed. NITNS significantly reduced IBS-SSS scores ( p = 0.0001) and increased IBS-QOL scores ( p < 0.0001). VAS ( p = 0.0003) and BSFS ( p < 0.00001) scores also improved significantly. HRV results suggested NITNS might influence the autonomic nervous system function. The incidence of AEs did not differ significantly between NITNS and sham-NITNS groups ( p = 0.64). Exploratory subgroup analysis indicated that differences in NITNS stimulation modalities and IBS subtypes might influence the therapeutic efficacy of NITNS. Overall evidence quality ranged from low to very low. Conclusion: NITNS is a safe and effective non-pharmacological intervention with potential value in the management of IBS. However, further large-scale, high-quality RCTs are needed to confirm their long-term efficacy and safety. Trial registration: PROSPERO CRD420251157617.
Wei et al. (Sun,) studied this question.