Prabhu Rajagopalan ¹ , Raksha Sunhare¹ , Shyamprasad Kodimule ¹ and Subhendu Nayak ² *

¹ Development and Research Centre-Probiotics, Vidya Herbs Pvt Ltd, No. 102B and 105B, Pharmaceuticals SEZ Industrial area, KIDB, Hassan, Karnataka, India
² Vidya USA Corporation, 7 Otis Stone Hunter Road, Bunnell, FL, USA

*Corresponding Author: Subhendu Nayak, Vidya USA Corporation, 7 Otis Stone Hunter Road, Bunnell, FL, USA.

Received: January 23, 2026; Published: February 18, 2026

Abstract

Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder marked by abdominal pain and altered bowel habits, often impairing quality of life. Gut microbiota dysbiosis is increasingly recognized as a contributor to IBS pathogenesis, positioning probiotics as a promising therapeutic approach. This randomized, double-blind, placebo-controlled, multicenter phase III study assessed the efficacy and safety of Bacillus coagulans (1 × 109 CFU/day) in adult IBS patients over 90 days. Sixty participants meeting Rome IV criteria were randomized 1:1 to receive probiotic or placebo. Efficacy endpoints included digestive symptom frequency (DSFQ), IBS severity (IBS-SSS), stool consistency (Bristol stool form scale), and health-related quality of life (FDDQL and FBA questionnaires), with safety monitored via laboratory tests and adverse events. Supplementation with B. coagulans significantly reduced DSFQ scores by 55.3%, normalized stool consistency in 66.7% of participants, and resolved IBS symptoms in 86.7% as per IBS-SSS. Quality of life improved across domains including activity limitation, anxiety, dietary restrictions, sleep quality, and stress impact, whereas the placebo group showed minimal changes. No serious adverse events occurred, and laboratory parameters remained normal. These results indicate that Bacillus coagulans is a safe, well-tolerated, and effective microbiome- targeted intervention for alleviating IBS symptoms and enhancing patient quality of life.

Keywords: Irritable Bowel Syndrome (IBS); Quality of Life; Bacillus coagulans

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Citation

Citation: Subhendu Nayak.,et al. “A Randomized, Double Blind, Placebo Controlled, Parallel, Multi-Center, Phase 3 Study on Genetic and Clinical Evalua- tion of Probiotic Bacillus coagulans Strain in Patients with Irritable Bowel Syndrome". Acta Scientific Nutritional Health 10.3 (2026): 11-17.

Copyright

Copyright: © 2026 Subhendu Nayak.,et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.