Interactions on record — worth a quick check against your medications. Based on 5 of 6 ingredients. Check your meds →
Dietary supplement

Chitosan With Glucomannan Ingredients & Drug Interactions

by GNC Total Lean

Chitosan With Glucomannan label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Chitosan With Glucomannan against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Chitosan With Glucomannan is a dietary supplement by GNC Total Lean with 6 active ingredients. Its ingredients are commonly taken for constipation, diarrhea, high cholesterol.Based on those ingredients, 2,053 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Dietary Fiber, Glucomannan powder, Inulin. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Chitosan With Glucomannan by GNC Total Lean

Ask about any prescription or over-the-counter medication and we check it for interactions with Chitosan With Glucomannan by GNC Total Lean — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Chitosan With Glucomannan by GNC Total Lean

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

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 12, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 2 of its 6 active ingredients.
  • “Proprietary Blend (Combination)” is a proprietary blend — the label gives one combined amount (400 mg) without saying how much of each component you get.

GNC Total Lean contains five active ingredients. Inulin and fructooligosaccharides are soluble fibers that work as prebiotic carbohydrates.

Chitosan is a fiber derived from shellfish shells. Glucomannan is another viscous fiber from the konjac plant root.

Psyllium seed husks powder is a plantain-derived fiber. Together, these five ingredients are designed to act as bulking and binding agents in the digestive tract.

The product also contains gelatin and cellulose as inactive ingredients (capsule material and filler).

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: promote fullness, support digestion and colon health.
  • We looked for evidence on: Constipation, Diarrhea, Hypercholesterolemia, Hyperlipidemia, Hypertriglyceridemia, Obesity — and 4 related terms.
  • The strongest evidence on file: Black Psyllium is rated "Effective" for Constipation (Natural Medicines).
  • Also on file: Glucomannan is rated "Possibly Effective" for Constipation, Hyperlipidemia.
  • Also on file: Chitosan is rated "Possibly Effective" for Obesity.

Inulin is possibly effective for constipation, obesity, and diabetes, though evidence is mixed on whether it actually lowers blood sugar. Chitosan is possibly effective for obesity and possibly for blood pressure and recovery after surgery.

Glucomannan is possibly effective for constipation, diabetes, and high cholesterol levels. Fructooligosaccharides and psyllium seed husks lack sufficient reliable evidence in our data to rate their effectiveness for any condition this product targets.

Keep in mind that most of these ratings reflect limited or mixed research; talk with your doctor about what results you can realistically expect.

The evidence, ingredient by ingredient Black Psyllium Inulin Fructo-oligosaccharides (fos) Glucomannan Chitosan

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

These ingredients are generally well tolerated short-term, but gastrointestinal side effects are common — bloating, gas, flatulence, constipation, diarrhea, nausea, and abdominal cramps, especially at higher doses or when taken without enough water. Glucomannan in particular can cause choking or blockage in the throat or gut if swallowed dry; always take it with plenty of liquid.

Inulin at doses over 30 grams daily increases GI symptoms. Chitosan is generally well tolerated but carries a rare risk of anaphylaxis if you have a shellfish allergy.

Pregnancy and breastfeeding: the data advises against chitosan use during pregnancy and while breastfeeding. For inulin, fructooligosaccharides, and glucomannan, safety data is limited; talk with your doctor before using during pregnancy or lactation.

No data is on file for psyllium seed husks in pregnancy or breastfeeding.

Side effects, ingredient by ingredient Black Psyllium Inulin Fructo-oligosaccharides (fos) Glucomannan Chitosan

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?
  • 4 of the 5 matched ingredients can interact with medications — Black Psyllium, Glucomannan, Chitosan, Inulin.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 2,054 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.

Double-check this product against warfarin (blood thinners) — chitosan can reduce clotting and increase bleeding risk. If you take acyclovir or other antivirals, ask your pharmacist, since chitosan may block their absorption.

Glucomannan can lower the absorption of oral medications in general, so space doses at least 2 hours apart from your prescriptions. If you take any diabetes medicine, note that inulin theoretically raises low-blood-sugar risk, though evidence is unclear.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This is a multi-fiber weight-loss and digestive-health product best suited for people without shellfish allergy and without prescriptions for blood thinners, antivirals, or most other oral medications. If you take warfarin, acyclovir, or any regular medication, check it against this product before starting.

Talk to your pharmacist or doctor about how much water to drink with it and whether GI side effects might be an issue for you.

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

Assessment coverage: 5 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated May 24, 2017.

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 Chitosan With Glucomannan, straight from the product label.

Brand GNC Total Lean
Barcode (UPC) 048107077709
Net contents 120 Capsule(s)
Market status On market
Date entered into DSLD May 24, 2017
DSLD ID 74394
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free
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 Chitosan With Glucomannan by GNC Total Lean, 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
60
UPC/BARCODE
048107077709
IngredientAmount% DV
Total Carbohydrates1 g1%
Dietary Fiber1 g4%
Inulin0 NP--
Fructooligosaccharides0 NP--
Proprietary Blend (Combination)400 mg--
Chitosan1000 mg--
Glucomannan powder0 NP--
Psyllium seed husks powder0 NP--

Other ingredients: Gelatin, Cellulose

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.
Formulation

No starch, no artificial colors, no artificial flavors, sodium free, no wheat, gluten free, no corn, no soy, no dairy, yeast free.

Precautions

Keep out of reach of children.

Warning: Taking this product without adequate fluid may cause it to swell and block your throat or esophagus and may cause choking. Do not take this product if you have difficulty in swallowing. If you experience chest pain, vomiting, or difficulty in swallowing or breathing after taking this product, seek immediate medical attention.

Consult your physician prior to using this product if you are pregnant, nursing, taking medication, or have a medical condition.

Discontinue use two weeks prior to surgery.

Contains: Crustaceans (shrimp).

Storage

Store in a cool, dry place.

FDA Statement of Identity

Dietary Supplement

General Statements

Proprietary fiber blend promotes a feeling of fullness + supports digestion and colon health

Scientifically formulated

General

CODE 484711 BRG

Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, take two capsules with at least 8 oz of water or other fluid, once or twice daily. Taking this product without enough liquid may cause choking. See warning.

FDA Disclaimer Statement

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

Formula

Contains: Crustaceans (shrimp).

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Chitosan With Glucomannan by GNC Total Lean label

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

Chitosan With Glucomannan label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Chitosan With Glucomannan by GNC Total Lean

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container60 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 g 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

Proprietary Blend (Combination)

400 mg per serving

Chitosan

Interacts with
3 drugs
1000 mg per serving

Chitosan is a fiber-like substance made from the shells of shrimp, crabs, and other shellfish, often marketed for weight loss and cholesterol. The evi...

Chitosan monograph & interactions

Other (inactive) ingredients: Gelatin, Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

Chitosan With Glucomannan by GNC Total Lean Drug Interactions

Want to check YOUR meds against Chitosan With Glucomannan?

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
2,053Drugs
2,022 Moderate 31 Minor

Ingredients driving the most interactions

Dietary Fiber 2,025
Glucomannan powder 2,022
Inulin 86
Chitosan 3

Individual Drug Interactions

The ingredients in Chitosan With Glucomannan interact with 2,053 drugs. Click any drug to see the details.

4 of the 6 ingredients in Chitosan With Glucomannan interact with drugs. Each result below shows which ingredient is responsible. Dietary Fiber Glucomannan powder Inulin Chitosan

Each ingredient & the kinds of drugs it affects

For each ingredient in Chitosan With Glucomannan 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
Dietary Fiber full monograph & interactions

Glucomannan powder1 drug type · 2,022 drugs

Oral Drugs

Theoretically, glucomannan may decrease absorption of drugs taken orally.
Due to its viscosity and bulking effects, there is concern that glucomannan can decrease the absorption of oral drugs. A small clinical study in healthy volunteers shows that taking glyburide 2.5 mg plus glucomannan 3.9 grams with breakfast reduces plasma levels of glyburide when compared with breakfast and glyburide alone. In addition, animal research demonstrates this effect on amoxicillin, but shows increased absorption of metronidazole. This mouse model also demonstrates that metronidazole elimination is prolonged, but amoxicillin elimination is enhanced by 38%; glucomannan may also affect the distribution of some drugs. To avoid changes in absorption, take glucomannan 30-60 minutes after taking oral drugs.

Likelihood Probable Evidence B
Glucomannan powder full monograph & interactions

Inulin1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, inulin might increase the risk of hypoglycemia with antidiabetes drugs.
Some clinical research shows that inulin improves glycemic control in patients with diabetes; however, it is unclear if it has hypoglycemic effects.

Likelihood Unlikely Evidence D
Inulin full monograph & interactions

Chitosan2 drug types · 3 drugs

Acyclovir (Zovirax)

Chitosan can reduce the absorption of acyclovir, potentially increasing the risk for treatment failure.
Clinical research in humans shows that taking chitosan along with acyclovir 200 mg reduces acyclovir absorption. Concomitant administration of chitosan 400 mg or 1000 mg reduced the acyclovir area under the curve (AUC) and peak plasma concentration by about 30% and 40%, respectively, compared with control. Concomitant administration with chitosan 1000 mg also increased time to peak concentration from 1 hour to 2 hours. In vitro research suggests that the mechanism for reduced absorption is due to acyclovir entrapment in chitosan-mucus complexes, which reduces intestinal absorption.

Likelihood Possible Evidence B
Warfarin (Coumadin)

Theoretically, chitosan might increase the risk of bleeding when taken with warfarin.
In a case report, a patient taking warfarin had a significantly increased international normalized ratio (INR) after starting chitosan 1200 mg daily. The INR normalized after chitosan was discontinued and vitamin K was administered. The patient once again started taking chitosan and again had a significant increase in INR. The INR stabilized again once chitosan was discontinued. Researchers theorize that this interaction might occur because chitosan decreases absorption of fat-soluble vitamins, including vitamin K, which could increase the anticoagulant effect of warfarin.

Likelihood Possible Evidence D
Chitosan full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Chitosan With Glucomannan, from the product label.

GNC Total Lean

See all GNC Total Lean products
Name
General Nutrition Corporation
City
Pittsburgh
State
PA
ZipCode
15222
Phone Number
1-888-462-2548
Web Address
gnc.com
Pharmacist Counseling Corner

Chitosan With Glucomannan by GNC Total Lean: Common Questions

Does Chitosan With Glucomannan by GNC Total Lean interact with any medications?
Yes. Based on its ingredients, Chitosan With Glucomannan has a known interaction with 2,053 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Chitosan With Glucomannan contains 6 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.
Does this product have a shellfish allergy warning?
Yes — chitosan is derived from shellfish shells, so if you have a shellfish allergy, avoid this product. A rare but serious reaction called anaphylaxis has been reported.
What's the main side effect I should expect?
Bloating, gas, and flatulence are the most common complaints, especially when you first start. Other GI side effects include constipation, diarrhea, nausea, and cramping. Taking it with plenty of water helps, and starting with a low dose may reduce symptoms.
Is it safe to take while pregnant or breastfeeding?
Chitosan is not safe during pregnancy or breastfeeding. For the other fibers — inulin, glucomannan, and fructooligosaccharides — safety data is limited. Talk with your doctor or pharmacist for personalized advice if you're pregnant or nursing.
Can I take this at the same time as my other pills?
No — glucomannan can reduce how much of your other oral medications your body absorbs. Space this product at least 2 hours away from any prescription drugs. Check your specific medications with your pharmacist first.
What does each ingredient actually do?
All five ingredients are fibers designed to add bulk and viscosity to your digestive tract — they're meant to help with weight loss, constipation, and blood sugar or cholesterol control. Inulin and fructooligosaccharides also feed beneficial gut bacteria.
Do I need to drink extra water with this?
Yes — absolutely. Glucomannan especially can cause choking or blockage if taken dry. Always swallow with plenty of liquid, and don't take it as a dry powder.

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

Not sure if Chitosan With Glucomannan is safe with your meds?

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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.

Chitosan With Glucomannan label
Go deeper

The Full Monographs Behind Chitosan With Glucomannan’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Black Psyllium

Interacts with 2,025 drugs

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. It is best known and most studied for rel...

Read the full Black Psyllium monograph → Herb & supplement monograph

Inulin

Interacts with 86 drugs

Inulin is a type of plant fiber (a prebiotic) found naturally in foods like chicory root, onions, and garlic, and it is widely added to supplements and processed foods. It may help with regu...

Read the full Inulin monograph → Herb & supplement monograph

Fructo-oligosaccharides (fos)

Fructo-oligosaccharides (FOS) are a type of soluble fiber that acts as a prebiotic, meaning they feed the helpful bacteria in your gut. They are generally considered safe for most people in...

Read the full Fructo-oligosaccharides (fos) monograph → Herb & supplement monograph

Glucomannan

Interacts with 2,022 drugs

Glucomannan is a soluble fiber from the konjac root that swells into a gel in your stomach, which may help with mild weight loss, constipation, and modestly lowering cholesterol. It is gener...

Read the full Glucomannan monograph → Herb & supplement monograph

Chitosan

Interacts with 3 drugs

Chitosan is a fiber-like substance made from the shells of shrimp, crabs, and other shellfish, often marketed for weight loss and cholesterol. The evidence for these benefits is weak, and an...

Read the full Chitosan monograph →
Sources

Sources & How We Checked

Chitosan With Glucomannan'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 73 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 →

Inulin 17 references
  1. Williams CM. Effects of inulin on lipid parameters in humans. J Nutr 1999 Jul;129(7 Suppl):1471S-3S. PubMed
  2. Pedersen A, Sandstrom B, Van Amelsvoort JM. The effect of ingestion of inulin on blood lipids and gastrointestinal symptoms in healthy females. Br J Nutr 1997;78:215-22. PubMed
  3. Cummings JH, Macfarlane GT, Englyst HN. Prebiotic digestion and fermentation. Am J Clin Nutr 2001;73:415S-420S. PubMed
  4. Bonnema AL, Kolberg LW, Thomas W, Slavin JL. Gastrointestinal tolerance of chicory inulin products. J Am Diet Assoc 2010;110(6):865-8. PubMed
  5. Dehghan P, Gargari BP, Jafar-Abadi MA, Aliasgharzadeh A. Inulin controls inflammation and metabolic endotoxemia in women with type 2 diabetes mellitus: a randomized-controlled clinical trial. Int J Food Sci Nutr 2014;65(1):117-23. PubMed
  6. Guess ND, Dornhorst A, Oliver N, Frost GS. A randomised crossover trial: the effect of inulin on glucose homeostasis in subtypes of prediabetes. Ann Nutr Metab 2016;68(1):26-34. PubMed
  7. Marteau P, Jacobs H, Cazaubiel M, Signoret C, Prevel JM, Housez B. Effects of chicory inulin in constipated elderly people: a double-blind controlled trial. Int J Food Sci Nutr 2011;62(2):164-70. PubMed
  8. Mensink MA, Frijlink HW, van der Voort Maarschalk K, Hinrichs WL. Inulin, a flexible oligosaccharide I: review of its physicochemical characteristics. Carbohydr Polym 2015;130:405-19. PubMed
  9. Slavin J, Feirtag J. Chicory inulin does not increase stool weight or speed up intestinal transit time in healthy male subjects. Food Funct. 2011;2(1):72-7. PubMed
  10. Micka A, Siepelmeyer A, Holz A, Theis S, Schön C. Effect of consumption of chicory inulin on bowel function in healthy subjects with constipation: a randomized, double-blind, placebo-controlled trial. Int J Food Sci Nutr. 2017;68(1):82-89. PubMed
  11. Smiljanec K, Mitchell CM, Privitera OF, Neilson AP, Davy KP, Davy BM. Pre-meal inulin consumption does not affect acute energy intake in overweight and obese middle-aged and older adults: A randomized controlled crossover pilot trial. Nutr Health. 2017;23 PubMed
  12. Cai X, Yu H, Liu L, et al. Milk powder co-supplemented with inulin and resistant dextrin improves glycemic control and insulin resistance in elderly type 2 diabetes mellitus: a 12-week randomized, double-blind, placebo-controlled trial. Mol Nutr Food Res PubMed
  13. Rao M, Gao C, Xu L, et al. Effect of inulin-type carbohydrates on insulin resistance in patients with type 2 diabetes and obesity: a systematic review and meta-analysis. J Diabetes Res. 2019;2019:5101423. PubMed
  14. Mitchell CM, Davy BM, Ponder MA, et al. Prebiotic Inulin Supplementation and Peripheral Insulin Sensitivity in adults at Elevated Risk for Type 2 Diabetes: A Pilot Randomized Controlled Trial. Nutrients 2021;13(9):3235. PubMed
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  16. Ziaei R, Shahshahan Z, Ghasemi-Tehrani H, Heidari Z, Ghiasvand R. Effects of inulin-type fructans with different degrees of polymerization on inflammation, oxidative stress and endothelial dysfunction in women with polycystic ovary syndrome: A randomized,
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See these in context on the Inulin monograph →

Fructo-oligosaccharides (fos) 6 references
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  2. Bouhnik Y, Vahedi K, Achour L, et al. Short-chain fructo-oligosaccharide administration dose-dependently increases fecal bifidobacteria in healthy humans. J Nutr 1999;129:113-6. PubMed
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  5. Andermann TM, Fouladi F, Tamburini FB, et al. A Fructo-Oligosaccharide Prebiotic Is Well Tolerated in Adults Undergoing Allogeneic Hematopoietic Stem Cell Transplantation: A Phase I Dose-Escalation Trial. Transplant Cell Ther 2021;27(11):932. PubMed
  6. Dou Y, Yu X, Luo Y, Chen B, Ma D, Zhu J. Effect of Fructooligosaccharides Supplementation on the Gut Microbiota in Human: A Systematic Review and Meta-Analysis. Nutrients 2022;14(16):3298. PubMed

See these in context on the Fructo-oligosaccharides (fos) monograph →

Chitosan 17 references
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  5. Mhurchu CN, Poppitt SD, McGill AT, et al. The effect of the dietary supplement, Chitosan, on body weight: a randomised controlled trial in 250 overweight and obese adults. Int J Obes Relat Metab Disord 2004;28:1149-56. PubMed
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  10. Schiller RN, Barrager E, Schauss EA, and et al. A randomized, double-blind, placebo-controlled study examining the effects of a rapidly soluble chitosan dietary supplement on weight loss and body composition in overweight and mildly obese individuals. J
  11. Koide, S. S. Chitin-chitosan: properties, benefits and risks. Nutrition Research 1998;8(6):1091-1101. DOI
  12. Maezaki Y, Tsuji K, Nakawa, and et al. Hypocholesterolaemic effect of chitosan in adult males. Biosc Biochem Biotech 1993;57:1439-1444.
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  16. Moraru C, Mincea MM, Frandes M, Timar B, Ostafe V. A meta-analysis on randomised controlled clinical trials evaluating the effect of the dietary supplement chitosan on weight loss, lipid parameters and blood pressure. Medicina (Kaunas). 2018;54(6):109. PubMed
  17. García MA, Hensler G, Al-Gousous J, Pielenhofer J, Wagner M, Lennernäs H, Langguth P. Novel food drug interaction mechanism involving acyclovir, chitosan and endogenous mucus. Drug Metab Pharmacokinet. 2023;49:100491. PubMed

See these in context on the Chitosan monograph →

Glucomannan 15 references
  1. Henry DA, Mitchell AS, Aylward J, et al. Glucomannan and risk of oesophageal obstruction. Br Med J 1986;292:591-2. PubMed
  2. Shima K, Tanaka A, Ikegami H, et al. Effect of dietary fiber, glucomannan, on absorption of sulfonylurea in man. Horm Metab Res 1983;15:1-3. PubMed
  3. Villaverde, A. F., Benlloch, S., Berenguer, M., Miguel, Rayon J., Pina, R., and Berenguer, J. Acute hepatitis of cholestatic type possibly associated with the use of glucomannan (amorphophalus konjac). J Hepatol. 2004;41(6):1061-1062. PubMed
  4. Yoshida, M., Vanstone, C. A., Parsons, W. D., Zawistowski, J., and Jones, P. J. Effect of plant sterols and glucomannan on lipids in individuals with and without type II diabetes. Eur.J Clin Nutr. 2006;60(4):529-537. PubMed
  5. Wood, R. J., Fernandez, M. L., Sharman, M. J., Silvestre, R., Greene, C. M., Zern, T. L., Shrestha, S., Judelson, D. A., Gomez, A. L., Kraemer, W. J., and Volek, J. S. Effects of a carbohydrate-restricted diet with and without supplemental soluble fiber
  6. Vanderbeek, P. B., Fasano, C., O'Malley, G., and Hornstein, J. Esophageal obstruction from a hygroscopic pharmacobezoar containing glucomannan. Clin Toxicol.(Phila) 2007;45(1):80-82. PubMed
  7. Bernstein, J. A., Crandall, M. S., and Floyd, R. Respiratory sensitization of a food manufacturing worker to konjac glucomannan. J Asthma 2007;44(8):675-680. PubMed
  8. Shichijo, K., Kobayashi, Y., Fueki, R., Shimoyama, K., and Masaya, M. [2 cases of konjac bronchial asthma found outside the "konnyaku" producing district]. Arerugi 1969;18(2):97-100.
  9. Carabin IG, Lyon MR, Wood S, et al. Supplementation of the diet with the functional fiber PolyGlycoplex is well tolerated by healthy subjects in a clinical trial. Nutr J 2009;8:9. PubMed
  10. Lyon MR, Reichert RG. The effect of a novel viscous polysaccharide along with lifestyle changes on short-term weight loss and associated risk factors in overweight and obese adults: an observational retrospective clinical program analysis. Altern Med Rev
  11. Lyon M, Wood S, Pelletier X, et al. Effects of a 3-month supplementation with a novel soluble highly viscous polysaccharide on anthropometry and blood lipids in nondieting overweight or obese adults. J Hum Nutr Diet 2011;24(4):351-9. PubMed
  12. Han Y, Zhang L, Liu XQ, Zhao ZJ, Lv LX. Effect of glucomannan on functional constipation in children: a systematic review and meta-analysis of randomised controlled trials. Asia Pac J Clin Nutr 2017;26(3):471-7.
  13. Health Canada Safety Alert. Health Canada Advises Canadians that natural health products containing glucomannan may cause serious choking if used with insufficient fluid. January 29, 2010. Alert # RA-110003825. https://healthycanadians.gc.ca/recall-alert-
  14. Mortensen A, Aguilar F, Crebelli, et al. EFSA Panel on Food Additives and Nutrient Sources added to Food. Re-evaluation of konjac gum (E 425 i) and konjac glucomannan (E425 ii) as food additives. EFSA Journal 2017;15(6):4864.
  15. Zhang Y, Aldamarany WAS, Song G, et al. Influence of konjac glucomannan and its derivatives on the oral pharmacokinetics of antimicrobial agent in antibiotics cocktails: Keep vigilant on dietary fiber supplement. Int J Biol Macromol 2023;251:126306. PubMed

See these in context on the Glucomannan 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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