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Psyllium

Brand names: Metamucil, Konsyl

Psyllium is a soluble fiber supplement that eases constipation, firms loose stools, and can modestly lower cholesterol.

Brand namesMetamucil, Konsyl
Type of medicineFiber supplement
Prescription?Over the counter
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

Increase slowly to avoid gas and bloating.

What it's used for

  • Constipation
  • Diarrhea (firming stools)
  • IBS
  • Lowering LDL cholesterol (modest)

How to take it

  • Mix with at least 8 ounces of water and drink right away.
  • Drink extra fluids through the day.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Gas
  • Bloating
Call 911Choking, chest pain, or trouble swallowing after taking it

Warnings

  • Don't take it dry or if you have trouble swallowing.

Other medicines, foods, and alcohol

  • Take other medicines 2 hours apart.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Generally safe in pregnancy.

Missed doses, overdose, and storage

If you miss a dose

This medicine is often taken only when needed. If you take it on a schedule, take a missed dose when you remember, unless it's almost time for the next one. Don't double up.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.