Supplement Forms/Alternate Names

  • Psyllium Fiber; Plantago ovate ; Plantaginis ovatae testa ; Plantaginis ovatae Semen; Indian Plantago; Ispagol; Ispaghul; Pale Psyllium; Spogel; Blonde Psyllium

Principal Proposed Uses

Other Proposed Uses

Psyllium is a fiber that comes from a plant called Plantago ovata (blonde psyllium). The plant has tiny, gel-coated seeds. Psyllium is found in the seeds’ husk. Psyllium is soluble, meaning that it can dissolve in water. When preparing psyllium for commercial use, the seeds are first harvested and cleaned. In some formulations, the husks are separated from the seeds and processed; in others, the husk remains intact. Black psyllium ( P. afra ), another variety of the seed, is also available.


Psyllium can be found as a dry seed or husk. It is a common ingredient in many popular laxatives and is available in powder, capsule, tablet, and wafer form. 1,15

Therapeutic Dosages

Dosages are specific to the product containing psyllium. Therefore, it is best to check the product label for the appropriate dosage. However, below is general dosage information for powdered psyllium.

Adults may take 3-6 grams of psyllium (1-2 teaspoons) in or with 8 ounces of water 2-3 times/day. 1 Always take psyllium with a full glass of water (8 ounces). Also, drinking 6-8 full glasses of water each day will help prevent constipation . 15

Children six years and older may take 1.5-3 grams of psyllium (1 teaspoon) in or with 4-8 ounces of water 2-3 times/day. 1

Do not take psyllium for longer than one week without first consulting your doctor. 26

Therapeutic Uses

Psyllium is primarily used to manage constipation, especially in people who do not eat enough fiber. It can be helpful for people who just had rectal surgery, are recovering from a heart attack , are on prolonged bed rest, or any other circumstance where straining during bowel movements is not advised. Patients experiencing other conditions where easy, soft bowel movements would be desirable (eg, anal fissures, hemorrhoids , pregnancy ) may find psyllium helpful. Finally, psyllium can also be used to treat certain kinds of watery diarrhea . 1

Psyllium works by mixing with water in the intestines to create a gel-like substance, which helps move bowels down the intestinal tract. 1

Psyllium has also been studied in the management of high cholesterol , high blood pressure , and diabetes .

What Is the Scientific Evidence for Psyllium?


A 2011 review of 3 trials with 283 subjects comparing psyllium (approximately 10 g daily) to placebo found consistently favorable results. 27 In one of the studies, for example, 2 weeks of psyllium (3.6 g, 3 times daily) produced a significantly greater improvement in symptoms over placebo. Numerous other studies have also shown psyllium to be effective in relieving constipation in adults. 8,10,11,12,13,23

Another small study looked at the effect of combining different laxatives to treat chronic constipation. Thirty-five men and women were randomized to either placebo or capsules containing celandine, aloe vera , and psyllium. Researchers found that those who had received the capsules had more frequent bowel movements and softer stools. 13

A larger study has also shown psyllium to effectively treat chronic constipation. The multi-site, randomized, double-blind study followed 170 adults with chronic constipation. The study compared psyllium and another laxative and found in favor of psyllium for better stool softening. 14 (However, this study was funded by the maker of a psyllium product.)


Some researchers have investigated psyllium’s ability to lower cholesterol, and conclusions have been mixed. 2,3,6,7,16,17,18,20,24 One study found that psyllium did not have a significant cholesterol-lowering effect in subjects with normal or slightly elevated cholesterol levels. However, two separate reviews of multiple studies found in favor of psyllium’s ability to reduce both total cholesterol and LDL (“bad”) cholesterol, particularly in subjects with mild to moderate elevations on low-fat diets. 2,24 An additional study found psyllium to have a modest but significant improvement for total and LDL cholesterol levels in people on low- or high-fat diets.

Another small study suggested that psyllium would be beneficial for postmenopausal women in lowering cholesterol and reducing the risk for heart diseases. 3

Irritable Bowel Syndrome

Fiber has long been a mainstay in the treatment of constipation in patients with irritable bowel syndrome. However, it is unclear which type of fiber is more beneficial, soluble (psyllium) or insoluble (eg, bran). Two studies suggest an answer. In a systematic review of 17 studies, the authors concluded that psyllium improved certain irritable bowel syndrome symptoms more than insoluble fibers. 9 This conclusion was supported by a subsequent randomized trial involving 275 adults, which found that psyllium was more effective than either bran or placebo for irritable bowel syndrome symptom relief. 22

Other Uses

Some studies have suggested psyllium may reduce blood pressure in individuals with hypertension 4,25 and improve glucose levels in patients with type 2 diabetes. 5,19,20

Safety Issues

Do not use psyllium if you have difficulty swallowing, unexplained abdominal pain, nausea , or vomiting. If you have kidney disease, talk to your doctor before taking psyllium. When consuming any type of fiber, gas and bloating are possible side effects. 15 Also, drink plenty of fluids when taking psyllium.

Some side effects specific to psyllium include cramps, difficulty swallowing, nausea, vomiting, skin rash, itching, and difficulty breathing. 1,26

Some people may be sensitive to psyllium. Try to avoid inhaling psyllium particles (eg, powder), since it may cause allergic reactions, such as difficulty breathing and itchy, red eyes. 21

Interactions You Should Know About

Since the absorption of many drugs can be affected by psyllium, talk to your doctor before using psyllium if you are taking any medicine. 1,15 Medicines of particular concern include:

Do not take psyllium at the same time you take your medicines. Psyllium should be taken at least two hours before taking your medicines or 2-4 hours afterward. 15,21

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