Last reviewed 2026-04-22 · How we verify

Psyllium powder

Psyllium powder absorbs water in the intestines to form a viscous gel that increases stool bulk and promotes regular bowel movements.

Psyllium powder absorbs water in the intestines to form a viscous gel that increases stool bulk and promotes regular bowel movements. Used for Constipation, Irritable bowel syndrome (IBS), Diarrhea.

At a glance

Mechanism of action

Psyllium is a soluble dietary fiber derived from Plantago ovata seeds. When mixed with water, it swells and creates a gelatinous mass that softens stool, increases fecal volume, and stimulates peristalsis. This mechanism helps normalize bowel function in both constipation and diarrhea by regulating intestinal transit time.

Approved indications

• Constipation
• Irritable bowel syndrome (IBS)
• Diarrhea
• Hypercholesterolemia (adjunctive)

Common side effects

• Bloating and gas
• Abdominal discomfort
• Allergic reactions (rare)

Key clinical trials

• Chronic Ingestion of Fructooligosaccharide and Psyllium on Intestinal Transit in Women With Functional Constipation: A Randomized Crossover Trial (NA)
• Ovolux Beauty From Within Trial#2 (NA)
• Eggshell Membrane Beauty From Within Trial (NA)
• The Role of Fiber in the Prevention and Treatment of Fecal Incontinence (NA)
• Efficacy of Dietary Fiber Supplementation (Soloways) in Patients With Specific Genetic Polymorphisms (NA)
• A Single-Group Study to Examine the Efficacy of a Gut Health Supplement to Increase Metabolism, Improve Gut Health, and Support Weight Management (NA)
• Examining the Efficacy of Fecal Microbiota Transplantation (FMT) and Dietary Fiber in Patients With Ulcerative Colitis (PHASE2)
• Effect of Methylcellulose or Psyllium on Fermentation of inUlin Assessed USing MRI (NA)

Primary sources

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