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Generic name: psyllium [ SIL-ee-um ]
Brand names: Hydrocil, Laxmar, Natural Fiber Therapy, Fiberall, Konsyl, ... show all 45 brands
Dosage forms: oral capsule (-; 400 mg; 500 mg; 525 mg), oral powder for reconstitution (100%; 2.4 g/3.7 g; 3.4 g/11 g; 3.4 g/12 g; 3.4 g/5.2 g; 3.4 g/5.4 g; 3.4 g/5.8 g; 3.4 g/7 g), ... show all 3 dosage forms
Drug class: Laxatives

Medically reviewed by on Jun 12, 2024. Written by Cerner Multum.

What is psyllium?

Psyllium is a bulk-forming fiber laxative that is used to treat occasional constipation or bowel irregularity.

Psyllium may also help lower cholesterol when used together with a diet low in cholesterol and saturated fat.

Psyllium may also be used for purposes not listed in this medication guide.

Psyllium side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Psyllium may cause serious side effects. Stop using psyllium and call your doctor at once if you have:

Common side effects of psyllium may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

You should not take psyllium if you have ever had an allergic reaction to it.

Ask a doctor or pharmacist if psyllium is safe to use if you have ever had:

This medicine may contain sugar, sodium, or phenylalanine. Check the medication label if you have diabetes, high blood pressure, phenylketonuria (PKU), or if you are on a low-salt diet.

Ask a doctor before using this medicine if you are pregnant or breastfeeding. Your dose needs may be different during pregnancy or while you are nursing.

Do not give psyllium to a child younger than 6 years old without medical advice.

How should I take psyllium?

Use exactly as directed on the label, or as prescribed by your doctor.

Laxatives may be habit-forming if they are used too often or for too long.

Psyllium can swell in your throat and cause choking if you don't take it with enough liquid. Drink plenty of fluids each day to help improve bowel regularity.

Take psyllium with a full glass (at least 8 ounces) of water or other liquid.

Swallow psyllium capsules one at a time.

Psyllium powder must be mixed with liquid before you take it. Do not swallow the dry powder. Mix with at least 8 ounces of liquid such as water or fruit juice. Stir and drink this mixture right away. Add a little more water to the glass, swirl gently and drink right away.

Psyllium usually produces a bowel movement within 12 to 72 hours.

Do not take psyllium for longer than 7 days in a row without a doctor's advice. Using a laxative too often or for too long may cause severe medical problems with your intestines.

Call your doctor if your symptoms do not improve, or if they get worse.

Psyllium may be only part of a complete program of treatment that also includes diet, exercise, and weight control. Follow your doctor's instructions very closely.

Store at room temperature away from moisture and heat. Keep the container tightly closed when not in use.

Psyllium dosing information

Usual Adult Dose for Constipation:

Daily fiber:
Adults 19 to 50 years: Male: 38 g/day; Female: 25 g/day
Pregnancy: 28 g/day
Lactation: 29 g/day

1 to 2 rounded teaspoonfuls, 1 to 2 packets, 1 to 2 wafers, or 5 to 6 capsules orally with 8 ounces of fluid 1 to 3 times a day

Usual Adult Dose for Irritable Bowel Syndrome:

Daily fiber:
Adults 19 to 50 years: Male: 38 g/day; Female: 25 g/day
Pregnancy: 28 g/day
Lactation: 29 g/day

1 to 2 rounded teaspoonfuls, 1 to 2 packets, 1 to 2 wafers, or 5 to 6 capsules orally with 8 ounces of fluid 1 to 3 times a day

Usual Pediatric Dose for Constipation:

Daily fiber:
Children 1 to 3 years: 19 g/day
Children 4 to 8 years: 25 g/day
Children 9 to 13 years: Male: 31 g/day; Female: 26 g/day
Children 14 to 18 years: Male: 38 g/day; Female: 26 g/day

Children 6 to 11 years: 1.25 to 15 g orally per day in divided doses
Children greater than or equal to 12 years and Adults: 2.5 to 30 g per day in divided doses

What happens if I miss a dose?

Since psyllium is used when needed, you may not be on a dosing schedule. Skip any missed dose if it's almost time for your next dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking psyllium?

Avoid breathing in the dust from psyllium powder when mixing. Inhaling psyllium dust may cause an allergic reaction.

If you take psyllium as part of a cholesterol-lowering treatment plan, avoid eating foods high in fat or cholesterol or your overall treatment will not be as effective.

What other drugs will affect psyllium?

Psyllium can make it harder for your body to absorb other medicines you take by mouth, possibly making them less effective. If you take any oral medicines, take them 2 hours before or 2 hours after you take psyllium.

Other drugs may affect psyllium, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.