Psyllium, often referred to as Asian Psyllium or by its botanical name Plantago ovata, is a soluble fiber commonly used as a bulk-forming laxative. Its use in the management of Irritable Bowel Syndrome (IBS) is supported by multiple clinical studies and is recommended in several clinical guidelines. Psyllium works by absorbing water in the intestine, increasing stool bulk, and facilitating smoother passage, which can help in both constipation-predominant and mixed-type IBS.

Randomized controlled trials have shown that psyllium supplementation can lead to significant improvements in overall IBS symptoms, particularly in stool frequency and consistency, and reduction of abdominal pain. A 2014 systematic review and meta-analysis published in the American Journal of Gastroenterology concluded that soluble fiber like psyllium is effective in improving global IBS symptoms compared to insoluble fiber or placebo.

Clinical guidelines, such as those from the American College of Gastroenterology and the British Society of Gastroenterology, typically recommend psyllium as a first-line dietary therapy for IBS, especially for constipation-dominant subtypes. It is generally well tolerated, though some individuals may experience bloating or gas. Thus, the use of psyllium for IBS is primarily justified by scientific validation, with robust evidence supporting its efficacy.