The Role of Colonic Microbiota in Constipation Predominant Irritable Bowel Syndrome: A Literature Review.

Irritable Bowel Syndrome with Constipation (IBS-C) is a functional gastrointestinal disorder characterised by abdominal pain, bloating, and altered bowel habits. Emerging research highlights the role of colonic microbiota in its pathophysiology, with IBS-C patients often exhibiting dysbiosis marked by reduced beneficial bacteria (Bifidobacterium, Lactobacillus) and increased inflammatory microbes (Enterobacteriaceae, Escherichia coli). Dysbiosis in IBS-C leads to reduced short-chain fatty acid production, impaired gut motility, and altered serotonin signalling, affecting peristalsis and sensitivity. It also increases intestinal permeability, inflammation, and gut-brain axis interactions, worsening pain and gastrointestinal dysfunction. These alterations impact gut motility, serotonin metabolism, and gut-brain axis signalling, contributing to IBS-C symptoms. Despite growing evidence, inconsistencies in study findings highlight the need for standardised research methods. Future studies should focus on long-term microbiota dynamics, targeted therapies, and personalised treatment strategies to improve symptom management and clinical outcomes. This review systematically summarises the changes in gut microbiota connected to IBS-C and provides a reference for future personalised treatment strategies.