Fiber Powders and Psyllium: 5 Things to Check Before You Stir One In

Fiber powders, capsules and gummies line the digestive aisle, and many contain psyllium, a fiber from plant seed husks. They’re cheap, widely available and often the first thing people try for constipation. A few label details make the difference between a scoop that helps and one that causes trouble.

1. Know what kind of product it is

MedlinePlus¹ describes psyllium as a bulk-forming laxative used to treat constipation.¹ NIDDK lists fiber supplements as one of several over-the-counter options, alongside osmotic laxatives, stool softeners and stimulant laxatives, which are generally kept for more severe cases.²

Adults should get 22 to 34 grams of fiber a day from all sources, depending on age and sex.³ A supplement adds to the fiber in your food.

2. Use enough water, every time

MedlinePlus¹ advises mixing powder with at least 8 ounces of liquid right before you drink it, and drinking at least 8 ounces with any form of psyllium. This helps prevent choking and helps it work.¹ NIDDK also notes that liquids help fiber work better.³

Stop and call your doctor right away if you have trouble swallowing or breathing, stomach pain, a rash, itching, nausea or vomiting.¹ Avoid breathing in the powder while you mix it, especially if you’re sensitive to it.¹

3. Space it from your medicines

MedlinePlus¹ says not to take psyllium within 3 hours of digoxin, salicylates such as aspirin, or nitrofurantoin, an antibiotic used for urinary infections.¹ If you take several daily medicines, ask your pharmacist to set a schedule that keeps fiber apart from them.

4. Start low and build up

NIDDK advises adding fiber a little at a time so your body can get used to the change.³ Start with a small serving and increase it gradually rather than jumping to the full dose.

5. Know when to stop and ask

MedlinePlus¹ advises not taking psyllium for longer than one week for constipation unless your doctor says to.¹ NIDDK suggests talking with your doctor if self-care isn’t working, if you feel you depend on laxatives, or if you take medicines that may cause constipation.²

If constipation started after a new prescription, bring the bottle to your next visit.

Try: “I’ve been using a fiber powder for constipation for a few weeks. Is that the right choice for me, and could any of my medicines be part of the problem?”

Bloated by Dinner includes a Belly Clock log and a Test-It list with a visit script. Use them to track bowel habits, fiber and fluids, and to bring a clear picture to your visit. See the book.