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Dietary supplement

Glucomannan (Konjac Root) Powder Ingredients & Drug Interactions

by TerraVita Premium Collection

Glucomannan (Konjac Root) Powder label
See full label image
Powder Category: Fiber And Other Nutrients
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 Glucomannan (Konjac Root) Powder 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

Glucomannan (Konjac Root) Powder is a dietary supplement by TerraVita Premium Collection with 1 active ingredient. Its ingredients are commonly taken for weight loss and appetite control, constipation, high cholesterol.Based on those ingredients, 2,022 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Glucomannan, Powder. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Glucomannan (Konjac Root) Powder by TerraVita Premium Collection

Ask about any prescription or over-the-counter medication and we check it for interactions with Glucomannan (Konjac Root) Powder by TerraVita Premium Collection — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Glucomannan (Konjac Root) Powder by TerraVita Premium Collection

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 30, 2026

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: glucomannan powder, a water-soluble dietary fiber from the konjac root. It works by absorbing water and forming a thick gel in your digestive tract, which bulks up stool and slows digestion.

There are no inactive ingredients listed.

Does it work?

Moderate 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

This product doesn't appear to be marketed for a specific use, so we graded Glucomannan's overall clinical evidence instead.

Moderate

Some clinical evidence supports Glucomannan for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredient's overall clinical evidence instead.
  • On file: Constipation — rated "Possibly Effective" (Natural Medicines).
  • On file: Diabetes — rated "Possibly Effective" (Natural Medicines).
  • On file: Hyperlipidemia — rated "Possibly Effective" (Natural Medicines).

The evidence supports glucomannan for constipation, diabetes, and high cholesterol (hyperlipidemia) — all rated possibly effective based on available research. For high blood pressure, the evidence we have isn't strong enough to draw conclusions either way.

The evidence, ingredient by ingredient Glucomannan

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 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Glucomannan is generally well tolerated when you drink plenty of water with it. The most common side effects are belly pain, bloating, constipation, diarrhea, gas, nausea, and vomiting — especially if you take more than 3 grams a day or don't drink enough liquid.

Rare but serious risks include choking and blockage in your esophagus or intestines, particularly if you swallow it dry or in tablet form. For pregnancy, there isn't enough reliable safety data to know whether it's okay — talk with your doctor before using it.

Little is known about breastfeeding safety either, so caution is advised and a conversation with your doctor or pharmacist is warranted.

Side effects, ingredient by ingredient Glucomannan

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?
  • 1 of the 1 matched ingredient can interact with medications — Glucomannan.
  • The most serious interaction on file is rated Moderate.
  • For scale: 2,023 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.

Check any oral medications you take — that's drugs taken by mouth (pills, tablets, capsules) — before starting this product. Glucomannan can reduce their absorption, making them less effective.

Space this supplement and your medications by at least 2 hours if possible, and ask your doctor or pharmacist for guidance on timing.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.

Glucomannan is a fiber supplement that may help with constipation, blood sugar control, and cholesterol, but its main drawback is a Moderate interaction with oral medications — it can reduce how much of your drugs your body absorbs. If you take any prescription or over-the-counter medications, check them against the tool on this page and talk with your doctor or pharmacist about spacing them away from this supplement.

Always take glucomannan with plenty of water to avoid choking or blockage.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Jun 22, 2023.

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 Glucomannan (Konjac Root) Powder, straight from the product label.

Brand TerraVita Premium Collection
Barcode (UPC) 064435113087
Net contents 4 Ounce(s)
Market status On market
Date entered into DSLD Jun 22, 2023
DSLD ID 290823
Product type Fiber And Other Nutrients
Supplement form Powder
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 Glucomannan (Konjac Root) Powder by TerraVita Premium Collection, 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:
0.25 Teaspoon(s)
Maximum serving Sizes:
0.25 Teaspoon(s)
Servings per container
113
UPC/BARCODE
064435113087
IngredientAmount% DV
Glucomannan, Powder1000 mg--

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.
FDA Statement of Identity

A Dietary Supplement

Brand IP Statement(s)

Copyright 2004 TerraVita - Distributed by ZooScape LLC, All Rights Reserved.

Suggested/Recommended/Usage/Directions

Directions Stir 1/4 of a teaspoon into a glass of water and consume 3 times daily, with meals.

General Statements

TerraVita is an exclusive line of premium natural products that use the finest, purest and most potent ingredients in the world. TerraVita's hallmarks are the highest possible standards of purity, potency, stability and freshness. All products are prepared with the greatest quality control, from raw materials through the entire manufacturing process, right up to the moment your product is sealed for freshness and shipped to you.

Please recycle!

FDA Disclaimer Statement

Statements not evaluated by FDA. Product not intended to diagnose, treat, cure, or prevent any disease.

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

See for yourself

Glucomannan (Konjac Root) Powder by TerraVita Premium Collection label

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

Glucomannan (Konjac Root) Powder 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 Glucomannan (Konjac Root) Powder by TerraVita Premium Collection

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size0.25 Teaspoon(s) Dosage formPowder Servings per container113 Amounts shown are per serving.

Glucomannan, Powder

Interacts with
2,022 drugs
1000 mg per serving Form: Konjac, Powder

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 mo...

Glucomannan, Powder monograph & interactions
Interaction report

Glucomannan (Konjac Root) Powder by TerraVita Premium Collection Drug Interactions

Want to check YOUR meds against Glucomannan (Konjac Root) Powder?

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
2,022Drugs
2,022 Moderate

Ingredients driving the most interactions

Glucomannan, Powder 2,022

Individual Drug Interactions

The ingredients in Glucomannan (Konjac Root) Powder interact with 2,022 drugs. Click any drug to see the details.

1 of the 1 ingredient in Glucomannan (Konjac Root) Powder interact with drugs. Each result below shows which ingredient is responsible. Glucomannan, Powder

Each ingredient & the kinds of drugs it affects

For each ingredient in Glucomannan (Konjac Root) Powder with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

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
The maker

Brand information

Manufacturer and brand details for Glucomannan (Konjac Root) Powder, from the product label.

TerraVita Premium Collection

See all TerraVita Premium Collection products
Name
TerraVita Fine Whole Herbs
City
Brampton
State
Ontario
Pharmacist Counseling Corner

Glucomannan (Konjac Root) Powder by TerraVita Premium Collection: Common Questions

Does Glucomannan (Konjac Root) Powder by TerraVita Premium Collection interact with any medications?
Yes. Based on its ingredients, Glucomannan (Konjac Root) Powder has a known interaction with 2,022 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Glucomannan (Konjac Root) Powder contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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.
What exactly is glucomannan and where does it come from?
Glucomannan is a water-soluble fiber extracted from the konjac root, a plant used for centuries in Asian cooking. When you take it with water, it forms a thick gel in your stomach and intestines, which helps bulk up stool and slow digestion.
Can I take glucomannan if I'm pregnant or breastfeeding?
There isn't enough safety data in pregnancy to say it's okay — talk with your doctor first. For breastfeeding, very little is known about safety, so caution is advised and checking with your doctor or pharmacist is the right call.
What side effects might I experience?
Most common are belly pain, bloating, gas, diarrhea, and nausea — especially if you take more than 3 grams daily or don't drink enough liquid. Rare but serious risks are choking and intestinal blockage, which happen mainly if you swallow it dry.
How much water should I drink with this supplement?
The facts emphasize taking it with plenty of water. Drinking too little liquid is the main reason people experience choking or blockage, so err on the generous side.
Does glucomannan actually work for high blood pressure?
The evidence we have isn't strong enough to know whether it helps with blood pressure, so that's one condition we can't reliably say it works for.
Why can't I just take this at the same time as my other medications?
Glucomannan forms a thick gel in your stomach that can slow or block the absorption of oral drugs, lowering how much of them your body takes in. Spacing them apart by at least 2 hours helps prevent that. Your doctor or pharmacist can advise on the best timing for your specific medications.

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

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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.

Glucomannan (Konjac Root) Powder label
Go deeper

The Full Monographs Behind Glucomannan (Konjac Root) Powder’s Ingredients

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

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 →
Sources

Sources & How We Checked

Glucomannan (Konjac Root) Powder'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 15 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.

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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