Interactions on record — worth a quick check against your medications. Based on 2 of 4 ingredients. Check your meds →
Dietary supplement

Tri-Fiber Complex Ingredients & Drug Interactions

by Swanson

Capsule Category: Fiber And Other Nutrients
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Tri-Fiber Complex is a dietary supplement by Swanson with 4 active ingredients. Its ingredients are commonly taken for constipation, diarrhea, high cholesterol.Based on those ingredients, 2,031 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Dietary Fiber, Apple Pectin, Powder. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Tri-Fiber Complex by Swanson

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 4 of its 4 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Tri-Fiber Complex has 3 active ingredients: psyllium husk powder, apple pectin powder, and oat bran. All three are soluble fibers that work by absorbing water in your digestive tract to add bulk and support regular bowel movement.

The product also contains gelatin, silica, magnesium stearate, and rice flour as inactive ingredients to hold the capsule together.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Supports bowel regularity and digestive health.
  • We looked for evidence on: Diarrhea, Hypercholesterolemia, Impaired glucose tolerance (Prediabetes), Constipation, Cholesterol management, Blood sugar control.
  • The strongest evidence on file: Black Psyllium is rated "Effective" for Constipation (Natural Medicines).
  • Also on file: Pectin is rated "Possibly Effective" for Hypercholesterolemia.
  • Also on file: Black Psyllium is rated "Insufficient Reliable Evidence To Rate" for Diabetes, Diarrhea.

Pectin has possibly effective evidence for high cholesterol (hypercholesterolemia). For blood sugar control or prediabetes, the evidence isn't established well enough to say whether it works.

We don't have effectiveness data on file for psyllium husk powder or oat bran in this product.

The evidence, ingredient by ingredient Black Psyllium Pectin

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Pectin from food and typical supplement doses is generally well tolerated. Most people who do experience side effects report gas, loose stools, diarrhea, or mild cramping.

Rarely, pectin can cause an allergic reaction, including anaphylaxis in sensitive individuals — and occupational inhalation of pectin dust can trigger asthma. For pregnancy and breastfeeding, the pectin in this product hasn't been well studied at supplement doses.

The safety data advises a conversation with your doctor or pharmacist before using it during pregnancy or while nursing — dietary amounts are probably fine, but concentrated supplements are a different question.

Side effects, ingredient by ingredient Black Psyllium Pectin

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 2 of the 2 matched ingredients can interact with medications — Black Psyllium, Pectin.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: heart-rhythm medications; lithium.
  • For scale: 2,032 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you take this, double-check if you're on digoxin (Lanoxin) for your heart, lovastatin for cholesterol, or any tetracycline antibiotic — all three have Moderate interactions with the pectin in this product and may become less effective.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This is worth considering if you're looking for fiber support and don't take digoxin, lovastatin, or tetracycline antibiotics. If you're on any heart or cholesterol medication, or any prescription at all, check with us first — fiber can change how some drugs work.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 16, 2022.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Tri-Fiber Complex, straight from the product label.

Brand Swanson
Barcode (UPC) 087614019932
Net contents 100 Capsule(s)
Market status On market
Date entered into DSLD Jun 16, 2022
DSLD ID 266989
Product type Fiber And Other Nutrients
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Tri-Fiber Complex by Swanson, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
50
UPC/BARCODE
087614019932
IngredientAmount% DV
Dietary Fiber1 Gram(s)2%
Calories5 Calorie(s)--
Total Carbohydrate1 Gram(s)--
Psyllium husk powder750 mg--
Apple Pectin, Powder40 mg--
Oat Bran710 mg--

Other ingredients: Gelatin, Silica, Magnesium Stearate, Rice Flour

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
General Statements

swanson.com or call 1-800-437-4148

Science-Backed Quality Since 1969

Formulation

Supports bowel regularity Helps with occasional constipation May support blood sugar balance Helps maintain healthy cholesterol levels

Digestive Health

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take two capsules two times per day with 8 ounces of water.

Precautions

Warning: For adults only.

Consult your healthcare provider before using this or any product if you are pregnant or nursing, taking medication or have a medical condition.

Keep out of reach of children.

Do not use if seal is broken.

Storage

Store in a cool, dry place.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Formula

Psyllium, Oat Bran and Apple Pectin

FDA Statement of Identity

Dietary Supplement

See for yourself

Tri-Fiber Complex by Swanson label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

What’s inside

The Ingredients in Tri-Fiber Complex by Swanson

These are the 4 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container50 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Dietary Fiber

Interacts with
2,025 drugs
1 Gram(s) per serving

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. I...

Dietary Fiber monograph & interactions

Psyllium husk powder

750 mg per serving

Apple Pectin, Powder

Interacts with
23 drugs
40 mg per serving

Pectin is a natural soluble fiber found in fruits like apples and citrus, and it is widely used in foods and as a fiber supplement. It may modestly he...

Apple Pectin, Powder monograph & interactions

Oat Bran

710 mg per serving Form: Avena sativa

Other (inactive) ingredients: Gelatin, Silica, Magnesium Stearate, Rice Flour. These complete the product’s ingredient list but are not active constituents.

Interaction report

Tri-Fiber Complex by Swanson Drug Interactions

Want to check YOUR meds against Tri-Fiber Complex?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

Go to the checker
2,031Drugs
46 Moderate 1,985 Minor

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in Tri-Fiber Complex with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Dietary Fiber7 drug types · 2,025 drugs

Carbamazepine (Tegretol)

Theoretically, black psyllium might reduce the effects of carbamazepine and increase the risk for convulsions.
Theoretically, black psyllium might reduce carbamazepine absorption. A preliminary study using blond psyllium reported decreased carbamazepine bioavailability due to binding of the drug to psyllium, as well as reduction of available fluid in the gut for dissolution of the drug. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Lithium

Theoretically, taking black psyllium at the same time as lithium might reduce lithium absorption.
The fiber in black psyllium might reduce lithium absorption and plasma levels. Some case reports describe a reduction in plasma lithium levels with concomitant administration of blond psyllium. This was reversed when psyllium was stopped. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Metformin (Glucophage)

Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Animal research shows that concurrent consumption of blond psyllium with metformin slows and increases the absorption of metformin. This interaction may also occur with black psyllium. To avoid changes in absorption, take psyllium 30-60 minutes after metformin.

Likelihood Possible Evidence D
Olanzapine (Zyprexa)

Theoretically, taking black psyllium at the same time as olanzapine might reduce olanzapine absorption.
The fiber in black psyllium might decrease the absorption of olanzapine. A single case report describes a reduction in the effectiveness of olanzapine when it was concomitantly administered with an unspecified type of psyllium 3 grams orally twice daily. This effect was reversed when psyllium was stopped.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, taking black psyllium at the same time as digoxin might reduce digoxin absorption and decrease digoxin levels.
Psyllium might bind digoxin in the gut. However, some clinical evidence suggests that psyllium does not impact digoxin absorption.

Likelihood Unlikely Evidence B
Ethinyl Estradiol

Theoretically, taking black psyllium at the same time as ethinyl estradiol might alter levels of estradiol.
Concurrent use of blond psyllium with ethinyl estradiol results in a slight increase in the extent of ethinyl estradiol absorption and a slower rate of absorption. This is unlikely to be clinically significant.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Psyllium seems to have variable effects on drug absorption. To avoid changes in absorption, take psyllium 30-60 minutes after oral medications. Animal research shows that blond psyllium delays and increases the absorption of metformin and ethinyl estradiol. Case reports and animal research suggest that blond psyllium might reduce absorption of lithium, digoxin, olanzapine, and carbamazepine. Finally, some pharmacokinetic studies show that psyllium does not affect the absorption of levothyroxine or warfarin. Although many of these studies evaluated blond psyllium, the fiber content in black psyllium may have similar effects.

Likelihood Possible Evidence B

Apple Pectin, Powder3 drug types · 23 drugs

Digoxin (Lanoxin)

Theoretically, pectin might reduce the absorption of digoxin, potentially decreasing its effectiveness.
A small clinical study shows that taking digoxin with a kaolin-pectin suspension reduces the absorption of digoxin by about 62%. It is unclear if these effects are due to pectin, kaolin, or the combination.

Likelihood Possible Evidence B
Lovastatin (Mevacor)

Theoretically, pectin might reduce the absorption of lovastatin, potentially decreasing its effectiveness.
Case reports suggest that concomitant use of pectin and lovastatin might reduce the cholesterol-lowering effect of lovastatin, possibly due to reduced intestinal absorption of lovastatin.

Likelihood Possible Evidence D
Tetracycline Antibiotics

Theoretically, pectin might reduce the absorption of tetracycline antibiotics, potentially decreasing their effectiveness.
A small clinical study shows that taking tetracycline with bismuth subsalicylate in a kaolin-pectin suspension reduces the absorption of tetracycline by about 34%. It is unclear if these effects are due to pectin, kaolin, bismuth subsalicylate, or the combination.

Likelihood Possible Evidence B
The maker

Brand information

Manufacturer and brand details for Tri-Fiber Complex, from the product label.

Swanson

See all Swanson products
Name
Swanson Health Products
City
Fargo
State
ND
ZipCode
58104
Phone Number
1-800-437-4148
Web Address
swanson.com
Pharmacist Counseling Corner

Tri-Fiber Complex by Swanson: Common Questions

Does Tri-Fiber Complex by Swanson interact with any medications?
Yes. Based on its ingredients, Tri-Fiber Complex has a known interaction with 2,031 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Tri-Fiber Complex contains 4 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Will this help lower my cholesterol?
Pectin, one of the three fibers in this product, has possibly effective evidence for high cholesterol. That means some studies suggest it may help, but the proof isn't rock solid yet. Talk to your pharmacist or doctor about whether it fits your cholesterol plan.
What side effects should I watch for?
Most people tolerate this well, but you might notice gas, loose stools, diarrhea, or mild cramping — especially when you first start taking it. If you have a history of food allergies or oral allergy syndrome, mention this to your pharmacist, because pectin can rarely trigger an allergic reaction.
Can I take this if I'm pregnant or breastfeeding?
The pectin in this supplement hasn't been well studied at concentrated doses during pregnancy or breastfeeding. Dietary fiber from food is fine, but talk with your doctor or pharmacist before adding this supplement — they can give you personalized advice based on your situation.
Can I take this with my heart medication?
If you take digoxin (Lanoxin), this product might reduce how much gets into your bloodstream, which could weaken its effect. Check with your pharmacist before starting — timing and spacing doses carefully may help, or you may need to avoid it.
What are the inactive ingredients?
The capsule contains gelatin, silica, magnesium stearate, and rice flour — all standard binders and fillers. If you're sensitive to any of these, let us know.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if Tri-Fiber Complex is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Tri-Fiber Complex label
Sources

Sources & How We Checked

Tri-Fiber Complex's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 29 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Black Psyllium 18 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
  4. Etman M. Effect of a bulk forming laxative on the bioavailablility of carbamazepine in man. Drug Dev Ind Pharm 1995;21:1901-6.
  5. Perlman BB. Interaction between lithium salts and ispaghula husk. Lancet 1990;335:416.
  6. Vaswani SK, Hamilton RG, Valentine MD, Adkinson NF. Psyllium laxative-induced anaphylaxis, asthma, and rhinitis. Allergy 1996;51:266-8. PubMed
  7. Lantner RR, Espiritu BR, Zumerchik P, Tobin MC. Anaphylaxis following ingestion of a psyllium-containing cereal. JAMA 1990;264:2534-6. DOI
  8. Kaplan MJ. Anaphylactic reaction to "Heartwise." N Engl J Med 1990;323:1072-3. DOI
  9. Nordstrom M, Melander A, Robertsson E, Steen B. Influence of wheat bran and of a bulk-forming ispaghula cathartic on the bioavailability of digoxin in geriatric in-patients. Drug Nutr Interact 1987;5:67-9..
  10. Robinson DS, Benjamin DM, McCormack JJ. Interaction of warfarin and nonsystemic gastrointestinal drugs. Clin Pharmacol Ther 1971;12:491-5. PubMed
  11. Garcia JJ, Fernandez N, Diez MJ, et al. Influence of two dietary fibers in the oral bioavailability and other pharmacokinetic parameters of ethinyloestradiol. Contraception 2000;62:253-7. PubMed
  12. Fernandez N, Lopez C, Díez R, et al. Drug interactions with the dietary fiber Plantago ovata husk. Expert Opin Drug Metab Toxicol 2012;8(11):1377-86.
  13. Semen plantaginis in: WHO Monographs on Selected Medicinal Plants, volume 1. World Health Organization, Geneva, 1999. Available at http://apps.who.int/medicinedocs/en/d/Js2200e/. Accessed November 26, 1026.
  14. Code of Federal Regulations, Title 21 (21CFR 101.17). Food labeling warning, notice, and safe handling statements. Available at www.ecfr.gov/cgi-bin/text-idx?SID=20f647d3b74161501f46564b915b4048&mc=true&node=se21.2.101_117&rgn=div8. Accessed December 3, 2
  15. Code of Federal Regulations, Title 21 (21CFR 201.319). Specific labeling requirements - water-soluble gums, hydrophilic gums, and hydrophilic mucilloids. Available at www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=201.319. Accessed Dece
  16. Diez R, Garcia JJ, Diez MJ, Sierra M, Sahagun AM, Fernandez N. Influence of Plantago ovata husk (dietary fiber) on the bioavailability and other pharmacokinetic parameters of metformin in diabetic rabbits. BMC Complement Altern Med. 2017 Jun 7;17(1):298. PubMed
  17. Chiu AC, Sherman SI. Effects of pharmacological fiber supplements on levothyroxine absorption. Thyroid. 1998;8(8):667-71. PubMed
  18. Merrick C, Madden CA, Capurso NA. A Case of Blunted Orally Disintegrating Olanzapine Effect Due to Coadministered Psyllium. J Clin Psychiatry 2021;82(2):20cr13633. PubMed

See these in context on the Black Psyllium monograph →

Pectin 11 references
  1. Jaakkola MS, et al. Asthma caused by occupational exposure to pectin. J Allergy Clin Immunol 1997;100:575-6. PubMed
  2. Westphal W, et al. [Exogenous allergic asthma following pectin exposure-a new occupational allergen]. Pneumologie 1990;44(Suppl 1):337-8.
  3. Baldwin JL, et al. Pectin-induced occupational asthma. Chest 1993;104:1936-7. PubMed
  4. Cohen AJ, Forse MS, Tarlo SM. Occupational asthma caused by pectin inhalation during the manufacture of jam. Chest 1993;103:309-11.
  5. Kraut A, et al. Christmas candy maker's asthma. IgG4-mediated pectin allergy. Chest 1992;102:1605-7. PubMed
  6. Richter WO, Jacob BG, Schwandt P. Interaction between fibre and lovastatin. Lancet 1991;338:706.
  7. Albert KS, Ayres JW, DiSanto AR, et al. Influence of kaolin-pectin suspension on digoxin bioavailability. J Pharm Sci 1978;67:1582-6. PubMed
  8. Albert KS, Welch RD, DeSante KA, et al. Decreased tetracycline bioavailability caused by a bismuth subsalicylate antidiarrheal mixture. J Pharm Sci 1979;68:586-8. PubMed
  9. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  10. Federal Register April 17,2003. Anti-Diarrheal Products for over-the-counter human use; final monograph. Available at: http://www.fda.gov/OHRMS/DOCKETS/98fr/03-9380.pdf (Accessed 27 December 2004).
  11. Washio K, Nakamura M, Sato N, et al. Anaphylaxis in a pectin- and cashew nut-allergic child caused by a citrus bath. Allergol Int 2022;71(1):155-157. PubMed

See these in context on the Pectin monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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