Journal of Gastroenterology

, Volume 52, Issue 4, pp 432–443

Efficacy of double-coated probiotics for irritable bowel syndrome: a randomized double-blind controlled trial

Original Article—Alimentary Tract

DOI: 10.1007/s00535-016-1224-y

Cite this article as:
Han, K., Wang, J., Seo, JG. et al. J Gastroenterol (2017) 52: 432. doi:10.1007/s00535-016-1224-y



The purpose of this study was to elucidate the effects of a dual-coated probiotic supplement (Duolac Care) on symptoms of diarrhea-predominant irritable bowel syndrome in a randomized double-blind clinical trial.


Fifty subjects with diarrhea-predominant irritable bowel syndrome were randomly assigned to either the non-coating group or the dual-coating group in order to receive two capsules per day of multi-species probiotics containing 5 billion bacteria per capsule for 4 weeks. Data from an adequate relief questionnaire were used in assessment of primary outcome. Daily records of stool frequencies and the Bristol stool scale, a weekly symptom diary using 100-mm visual analog scale, and Beck depression inventories were collected. Blood tests including blood cell counts, interleukin-10, tumor necrosis factor-alpha and inducible nitric oxide synthase, and regulatory T cells—CD4 + CD25high T cells, CD4 + LAP + T cells and CD25high + LAP + T cells—were analyzed before and after the study. The shift of gut microbiota was investigated using a quantitative real-time polymerase chain reaction assay.


Responses to the adequate relief questionnaire indicated significant improvement in overall discomfort in the dual-coating group and the ratio of normal stools to hard or watery stools had a better effect from dual-coated probiotics compared to non-coated probiotics. This may be due to a shift of intestinal microbiota, as our correlation analysis showed significant negative correlation between Bifidobacterium and urgency of defecation.


Our result implies that dual-coating layers of probiotic supplement can be a candidate for treatment of diarrhea-predominant irritable bowel syndrome.


Probiotics Irritable bowel syndrome Dual-coating technology 

Supplementary material

535_2016_1224_MOESM1_ESM.docx (33 kb)
Supplementary material 1 (DOCX 33 kb)

Copyright information

© Japanese Society of Gastroenterology 2016

Authors and Affiliations

  • Kyungsun Han
    • 1
  • Jinghwa Wang
    • 1
  • Jae-Gu Seo
    • 2
  • Hojun Kim
    • 1
  1. 1.Department of Rehabilitation Medicine of Korean MedicineDongguk University Ilsan HospitalGoyangRepublic of Korea
  2. 2.R&D Center, Cell Biotech Co. Ltd.GimpoRepublic of Korea

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