ACTION Trial
Clinical knowledge base written and curated by GastroAGI Team from primary medical literatureLast updated October 1, 2025
The ACTION trial was a significant clinical study designed to evaluate the efficacy and safety of acupuncture in treating diarrhea-predominant irritable bowel syndrome (IBS-D). Below is a detailed summary of the trial:
Background
- Global burden of IBS-D: IBS affects approximately 4.1% of adults worldwide, with IBS-D accounting for about one-third of all cases. It is associated with frequent loose stools, abdominal pain, reduced quality of life, and considerable psychological and socioeconomic burden.
- Limitations of standard therapies: Common treatments, including dietary modifications, medications, and cognitive behavioral therapy, often provide incomplete relief, come with side effects, or lead to symptom recurrence.
- Rationale for acupuncture: Acupuncture has long been used for gastrointestinal disorders, but high-quality evidence supporting its efficacy for IBS-D has been limited.
Objective
The ACTION trial aimed to determine whether acupuncture could improve abdominal pain and stool consistency in IBS-D patients compared to sham acupuncture.
Study Design
- Type of trial: Multicenter, randomized, sham-controlled clinical trial.
- Location: Conducted across six hospitals in China.
- Timeline: May 2021 to August 2022.
- Participants:
- A total of 584 adults were screened.
- 280 adults aged 18–75 who met the Rome IV criteria for IBS-D were randomized equally into two groups: acupuncture and sham acupuncture.
Treatment Protocol
- Duration: Participants received 15 sessions over six weeks:
- Three sessions per week during weeks 1–3.
- Two sessions per week during weeks 4–6.
- Administration: All sessions were conducted by licensed acupuncturists.
Acupuncture Group
- Acupoints: Needles were placed at eight fixed points (CV12, CV4, ST25, ST36, ST37) and one optional bilateral pair (LR3, SP6, or ST44).
- Technique: Manual stimulation was applied to elicit the "deqi" sensation, which is a characteristic feeling of needle insertion in acupuncture.
Sham Control Group
- Procedure: Participants received identical adhesive pads, but no needles were inserted or stimulated.
- Rescue medication: Loperamide was allowed for both groups as needed.
Primary Endpoint
- Composite response at week 6: Defined as:
- A ≥30% reduction in the worst abdominal pain.
- A ≥50% reduction in diarrhea days from baseline.
Key Results
Primary Outcome
- At week 6, 57.9% of acupuncture patients achieved the primary endpoint compared to 41.4% in the sham group.
- Relative Risk (RR): 1.40
- Statistical significance: P = 0.008.
Sustained Efficacy
- Improvements were observed as early as week 3 and remained significant through week 18.
- Per-protocol analysis confirmed the findings:
- 58.7% of acupuncture patients vs. 41.0% of sham patients achieved the primary endpoint (P = 0.011).
Stool Consistency
- Acupuncture group: Mean days with loose stools decreased from 5.1 to 2.1.
- Sham group: Mean days decreased from 5.2 to 3.0.
- Significant between-group differences were evident from week 5 onward.
Abdominal Pain Relief
- Both groups showed improvement, but the acupuncture group achieved greater long-term reductions:
- By week 18: −2.54 (acupuncture) vs. −1.99 (sham); P = 0.012.
IBS Symptom Severity
- The IBS Symptom Severity Scale (IBS-SSS) improved more in the acupuncture group:
- Acupuncture: −127.3.
- Sham: −89.3.
- P < 0.001.
- Benefits were sustained at the 12-week follow-up.
Adequate Relief Perception
- 61.4% of acupuncture patients reported adequate relief compared to 35.0% in the sham group (P < 0.001).
- Differences were noticeable from week 2 onward.
Responder Rates
- 83% of acupuncture patients achieved a ≥50-point reduction in IBS-SSS compared to 68.4% in the sham group (P = 0.004).
Secondary Outcomes
- Quality of Life (IBS-QOL): No significant differences between groups.
- Psychological outcomes (e.g., PHQ-9 for depression): No significant differences.
- Bloating and stool frequency: No significant differences between groups.
Safety and Tolerability
- Adverse events: Mild and transient, primarily:
- Minor bleeding (11.3%).
- Post-needling pain (5.7%).
- No serious adverse events were reported.
Conclusion
The ACTION trial demonstrated that acupuncture significantly improved:
- Abdominal pain.
- Stool consistency.
- Global symptom relief.
- IBS severity.
These benefits were durable, lasting up to 18 weeks, and acupuncture was well-tolerated with a favorable safety profile. This study provides robust evidence supporting the use of acupuncture as an effective treatment option for IBS-D.
