Interactions on record — worth a quick check against your medications. Based on 7 of 9 ingredients. Check your meds →
Dietary supplement

Glucomannan+ Ingredients & Drug Interactions

by Swanson

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 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

Glucomannan+ is a dietary supplement by Swanson with 9 active ingredients. Its ingredients are commonly taken for constipation and bowel regularity, diarrhea (as a stool bulking agent), lowering cholesterol.Based on those ingredients, 2,124 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Guar Gum, Konjac Glucomannan, Gymnema sylvestre Leaf Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Glucomannan+ by Swanson

Ask about any prescription or over-the-counter medication and we check it for interactions with Glucomannan+ by Swanson — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Glucomannan+ 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

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 9 of its 9 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Glucomannan+ contains 9 ingredients, with 7 active ones we could review. The primary active ingredients are guar gum and konjac glucomannan—both soluble fibers that absorb water and bulk up in your digestive tract to support regularity and cholesterol and blood sugar management.

The product also contains chromium, a mineral that plays a role in blood sugar control; apple pectin, a fiber from apples; L-carnitine, an amino acid involved in energy production; gymnema sylvestre leaf extract, used in traditional medicine for blood sugar support; and chitosan (LipoSan Ultra), a fiber derived from shellfish that may support fat metabolism. Oat bran fiber and psyllium husk fiber round out the fiber content.

The inactive ingredients are gelatin, calcium palmitate, rice flour, and silica—standard capsule fillers and flow agents.

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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Blood sugar support and weight management.
  • We looked for evidence on: Diabetes, Impaired glucose tolerance (Prediabetes), Constipation, Diarrhea, Hypercholesterolemia, Hyperlipidemia — and 4 related terms.
  • The strongest evidence on file: Glucomannan is rated "Possibly Effective" for Constipation (Natural Medicines).
  • Also on file: Glucomannan is rated "Possibly Effective" for Diabetes, Hyperlipidemia.
  • Also on file: Pectin is rated "Possibly Effective" for Hypercholesterolemia.

Guar gum is possibly effective for high blood pressure, high cholesterol, and irritable bowel syndrome (IBS), and possibly effective for constipation. Chromium is likely effective for chromium deficiency and possibly effective for type 2 diabetes, but the evidence suggests it's possibly ineffective for prediabetes.

Apple pectin is possibly effective for high cholesterol; the evidence for prediabetes and radiation exposure isn't established. L-carnitine is effective for L-carnitine deficiency and possibly effective for high triglycerides, heart failure, and angina.

Gymnema's effectiveness for diabetes, prediabetes, obesity, and metabolic syndrome isn't established in the data we hold. Konjac glucomannan is possibly effective for constipation, diabetes, and high cholesterol.

Chitosan is possibly effective for obesity, recovery after surgery, and high blood pressure; evidence for Crohn disease and dry eye is insufficient. Oat bran and psyllium husk fiber effectiveness data are not on file for this product.

The evidence, ingredient by ingredient Guar Gum Chromium Pectin L-carnitine Gymnema 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 7 of the 7 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 7 of 7.
  • General safety write-ups exist for 7 of 7.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Guar gum and konjac glucomannan must be taken with plenty of water to avoid choking or blockage—a serious but rare risk. Common side effects from these fibers include abdominal pain, bloating, gas, diarrhea, and loose stools; side effects can be minimized by starting with small doses and increasing gradually.

Chromium is generally well tolerated at typical doses but can cause gastrointestinal irritation, headaches, insomnia, and mood changes; high or long-term doses may pose risks. Apple pectin is generally well tolerated from food and typical supplement amounts; side effects may include diarrhea, gas, and mild cramps.

L-carnitine commonly causes abdominal discomfort, diarrhea, nausea, and a fishy body odor; seizures are rare. Gymnema is generally well tolerated short-term but can lower blood sugar.

Chitosan is generally well tolerated short-term and may cause constipation, diarrhea, gas, and nausea. For pregnancy: guar gum, chromium, and konjac glucomannan have limited pregnancy data—check with your doctor.

Gymnema and chitosan should be avoided in pregnancy due to insufficient safety data. Chromium from food and prenatal vitamins is generally acceptable, but extra supplement doses should be avoided unless your doctor recommends it.

For breastfeeding: data is limited or absent for most ingredients. L-carnitine is possibly safe while breastfeeding; gymnema and chitosan should be avoided.

Talk to your doctor or pharmacist before using this product if you are pregnant or nursing.

Side effects, ingredient by ingredient Guar Gum Chromium Pectin L-carnitine Gymnema 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?
  • 7 of the 7 matched ingredients can interact with medications — Glucomannan, Pectin, Chitosan, Gymnema, Guar Gum, among others.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; heart-rhythm medications.
  • For scale: 2,125 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 taking this product, check with your doctor or pharmacist about oral medications generally (especially penicillin and metformin), diabetes drugs and insulin, blood thinners like warfarin, thyroid hormone and levothyroxine, cholesterol-lowering drugs like lovastatin, tetracycline antibiotics, heart medications like digoxin, antiviral drugs like acyclovir, and NSAIDs like ibuprofen or aspirin. The most serious interactions are with oral drug absorption and blood thinners, but several other medication types can be affected by ingredients in this blend.

Check your own medication Run your meds through the checker above

The bottom line

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

Glucomannan+ may be worth considering if you're looking for a fiber supplement to support digestion, cholesterol, or blood sugar—but only if you don't take medications that are sensitive to absorption timing. The strongest caution is for anyone on oral antibiotics, diabetes medications, blood thinners, thyroid hormone, or heart medications like digoxin; this product could interfere with how well those drugs work.

Take this page to your doctor or pharmacist before starting, and be sure to take it well separated from other medications.

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

Assessment coverage: 7 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 22, 2024.

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+, straight from the product label.

Brand Swanson
Barcode (UPC) 087614040905
Net contents 300 Capsule(s)
Market status On market
Date entered into DSLD Mar 22, 2024
DSLD ID 308585
Product type Other Combinations
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 Glucomannan+ 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
150
UPC/BARCODE
087614040905
IngredientAmount% DV
Calories5 Calorie(s)--
Total Carbohydrates1 Gram(s)1%
Guar Gum200 mg--
Chromium100 mcg285%
Apple Pectin200 mg--
L-Carnitine20 mg--
Gymnema sylvestre Leaf Extract50 mg--
Konjac Glucomannan300 mg--
LipoSan Ultra200 mg--
Oat Bran Fiber200 mg--
Psyllium Husk Fiber200 mg--

Other ingredients: Gelatin, Calcium Palmitate, Rice Flour, Silica

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

Total wellness for mind, body & home Unsurpassed purity & potency 100% money back guaranteed

Digestive health

Brand IP Statement(s)

Swanson Science-backed quality since 1969

Chromax is a registered trademark of Nutrition 21 and is licensed under U.S. patents #5,087,623; #5,087,624; and #5,175,156. LipoSan ULTRA is a registered trademark of Primex ehf.

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take two capsules before each meal with a full 8-ounce glass of water or as recommended by your healthcare provider.

Formula

Chromax Chromium picolinate LipoSan ULTRA

Glucomannan with psyllium, oat bran & more Konjac root

Precautions

Warning: For adults only. Keep out of reach of children.

Consult your healthcare provider before use if you are pregnant, nursing or taking prescription medications, especially medications that affect blood sugar levels. Because this formula may enhance sensitivity to insulin and affect glucose levels, diabetics and hypoglycemics should consult their healthcare provider before using this product.

Do not use if seal is broken.

Contains shellfish (shrimp).

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.

FDA Statement of Identity

Dietary Supplement

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

See for yourself

Glucomannan+ by Swanson label

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

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 Glucomannan+ by Swanson

These are the 9 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container150 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.

Guar Gum

Interacts with
2,025 drugs
200 mg per serving

Guar gum is a soluble, gel-forming fiber from the guar bean that may modestly help with cholesterol, blood sugar, and bowel regularity. It is generall...

Guar Gum monograph & interactions

Chromium

Interacts with
178 drugs
100 mcg per serving Form: Chromax

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control i...

Chromium monograph & interactions

Apple Pectin

Interacts with
23 drugs
200 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 monograph & interactions

L-Carnitine

Interacts with
19 drugs
20 mg per serving Form: L-Carnitine Tartrate

L-carnitine is a compound your body makes naturally and also gets from foods like meat. It helps cells turn fat into energy, and supplements are most...

L-Carnitine monograph & interactions

Gymnema sylvestre Leaf Extract

Interacts with
851 drugs
50 mg per serving Form: Gymnemic Acids

Gymnema is an Ayurvedic herb best known for possibly helping lower blood sugar and reducing the taste of sweetness on the tongue. Some early human stu...

Gymnema sylvestre Leaf Extract monograph & interactions

Konjac Glucomannan

Interacts with
2,022 drugs
300 mg per serving

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...

Konjac Glucomannan monograph & interactions

LipoSan Ultra

Interacts with
3 drugs
200 mg per serving Form: Chitosan

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...

LipoSan Ultra monograph & interactions

Oat Bran Fiber

200 mg per serving

Psyllium Husk Fiber

200 mg per serving Form: Plantago ovata

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

Interaction report

Glucomannan+ by Swanson Drug Interactions

Want to check YOUR meds against 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
2,124Drugs
2,075 Moderate 49 Minor

Ingredients driving the most interactions

Guar Gum 2,025
Konjac Glucomannan 2,022
Gymnema sylvestre Leaf Extract 851
Chromium 178
Apple Pectin 23

Individual Drug Interactions

The ingredients in Glucomannan+ interact with 2,124 drugs. Click any drug to see the details.

7 of the 9 ingredients in Glucomannan+ interact with drugs. Each result below shows which ingredient is responsible. Guar Gum Konjac Glucomannan Gymnema sylvestre Leaf Extract Chromium Apple Pectin L-Carnitine LipoSan Ultra

Each ingredient & the kinds of drugs it affects

For each ingredient in 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.

Guar Gum5 drug types · 2,025 drugs

Ethinyl Estradiol

Theoretically, guar gum might reduce the absorption of ethinyl estradiol, potentially decreasing its effectiveness.
Animal research shows that taking guar gum with ethinyl estradiol decreases ethinyl estradiol absorption. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Metformin (Glucophage)

Guar gum might reduce the absorption of metformin, potentially decreasing its effectiveness.
A small study in healthy volunteers shows that guar gum reduces the absorption rate of metformin.

Likelihood Probable Evidence B
Oral Drugs

Guar gum might reduce the absorption of some oral drugs, potentially decreasing their effectiveness.
Clinical research shows that guar gum reduces or slows absorption of medications such as penicillin and metformin. To avoid changes in absorption, take guar gum 30-60 minutes after oral medications.

Likelihood Possible Evidence B
Penicillin

Guar gum might reduce the absorption of penicillin, potentially decreasing its effectiveness.
A small clinical study in healthy volunteers shows that taking guar gum with penicillin results in decreased penicillin absorption and reduced penicillin levels.

Likelihood Probable Evidence B
Digoxin (Lanoxin)

Guar gum might slow digoxin absorption, but it does not seem to impact how much digoxin is absorbed overall.
Two small studies in healthy volunteers show no change in the overall extent of digoxin absorption, although early absorption was slowed, when taken with guar gum.

Likelihood Possible Evidence B
Guar Gum full monograph & interactions

Konjac Glucomannan1 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
Konjac Glucomannan full monograph & interactions

Gymnema sylvestre Leaf Extract6 drug types · 851 drugs

Antidiabetes Drugs

Theoretically, taking gymnema with antidiabetes drugs might increase the risk of hypoglycemia.
Gymnema reduces blood glucose levels in some human and animal research. In human studies, it has been shown to enhance the blood glucose lowering effects of hypoglycemic drugs. However, other research in adults with prediabetes or metabolic syndrome suggests that gymnema does not reduce fasting levels of blood glucose. Until more is known, monitor blood glucose levels closely.

Likelihood Probable Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, gymnema might increase levels of drugs metabolized by CYP1A2.
Animal and in vitro research shows that gymnema can inhibit the CYP1A2 enzyme. In one animal study, oral administration of gymnema for 7 days increased the plasma concentrations of phenacetin, a CYP1A2 substrate, by about 1.4-fold and reduced the clearance of phenacetin by about 29%.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, gymnema might increase or decrease levels of drugs metabolized by CYP2C9.
Animal research shows that gymnema can induce the CYP2C9 enzyme. In one animal study, gymnema caused a 2.4-fold increase in the clearance of tolbutamide, a CYP2C9 substrate, in rats. In vitro research also shows that gymnema can inhibit CYP2C9.

Likelihood Possible Evidence D
Phenacetin

Theoretically, taking gymnema with phenacetin might increase the levels of phenacetin.
Animal research shows that gymnema, administered orally for 7 days, decreases the clearance of phenacetin in a dose-dependent manner by about 21% to 29% and increases plasma levels about 1.3- to 1.4-fold when compared to control.

Likelihood Possible Evidence D
Tolbutamide (Orinase)

Theoretically, taking gymnema with tolbutamide might the decrease levels of tolbutamide.
Animal research shows that gymnema, administered orally for 7 days, increases the clearance of tolbutamide by 2.4-fold when compared to control.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, gymnema might increase levels of drugs metabolized by CYP3A4.
One in vitro study using rat liver microsomes shows that gymnema can modestly inhibit the CYP3A4 enzyme. However, other in vitro research using human liver microsomes shows that gymnema does not affect CYP3A4 activity. Animal research also shows that gymnema does not alter the function of CYP3A4. In one study in rats, oral administration of gymnema for 7 days did not alter the clearance of amlodipine, a CYP3A4 substrate.

Likelihood Unlikely Evidence D
Gymnema sylvestre Leaf Extract full monograph & interactions

Chromium5 drug types · 178 drugs

Antidiabetes Drugs

Theoretically, chromium may have additive effects with antidiabetic agents and increase the risk of hypoglycemia.
Some research shows that taking chromium might lower blood glucose levels, especially in patients with poorly controlled type 2 diabetes.

Likelihood Possible Evidence A
Insulin

Theoretically, concomitant use of chromium and insulin might increase the risk of hypoglycemia.
In clinical research, chromium has been shown to increase insulin sensitivity,

Likelihood Possible Evidence B
Levothyroxine (Synthroid, Others)

Chromium might bind levothyroxine in the intestinal tract and decrease levothyroxine absorption.
Clinical research in healthy volunteers shows that taking chromium picolinate 1000 mcg with levothyroxine 1 mg decreases serum levels of levothyroxine by 17% when compared to taking levothyroxine alone. Advise patients to take levothyroxine at least 30 minutes before or 3-4 hours after taking chromium.

Likelihood Probable Evidence B
Aspirin

Theoretically, aspirin might increase chromium absorption.
Animal research suggests that aspirin may increase chromium absorption and chromium levels in the blood.

Likelihood Possible Evidence D
Nonsteroidal Anti-Inflammatory Drugs (Nsaids)

NSAIDs might increase chromium levels in the body.
Drugs that are prostaglandin inhibitors, such as NSAIDs, seem to increase chromium absorption and retention.

Likelihood Possible Evidence D
Chromium full monograph & interactions

Apple Pectin3 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
Apple Pectin full monograph & interactions

L-Carnitine3 drug types · 19 drugs

Acenocoumarol (Sintrom)

Theoretically, L-carnitine might increase the anticoagulant effects of acenocoumarol.
L-carnitine might enhance the anticoagulant effects of acenocoumarol, an oral anticoagulant similar to warfarin, but shorter-acting. There are at least two case reports of INR elevation with concomitant use. In one case, a 33-year-old male with a previously stable INR had an elevated INR of 4.65 after L-carnitine was started and continued for 10 weeks. INR normalized after discontinuation of the L-carnitine-containing product.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, L-carnitine might decrease the effectiveness of thyroid hormone replacement.
L-carnitine appears to act as a peripheral thyroid hormone antagonist by inhibiting entry of thyroid hormone into the nucleus of cells. Taking L-carnitine also seems to diminish some of the symptoms of hyperthyroidism.

Likelihood Probable Evidence B
Warfarin (Coumadin)

Theoretically, L-carnitine might increase the anticoagulant effects of warfarin.
L-carnitine might increase the anticoagulant effects of acenocoumarol, a shorter-acting oral anticoagulant similar to warfarin. There is not enough information to know whether this interaction occurs with L-carnitine and warfarin.

Likelihood Possible Evidence D
L-Carnitine full monograph & interactions

LipoSan Ultra2 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
LipoSan Ultra full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Glucomannan+, 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

Glucomannan+ by Swanson: Common Questions

Does Glucomannan+ by Swanson interact with any medications?
Yes. Based on its ingredients, Glucomannan+ has a known interaction with 2,124 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Glucomannan+ contains 9 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.
Can I take Glucomannan+ if I'm on blood pressure or blood sugar medication?
Not safely without checking first. Guar gum and konjac glucomannan can reduce how well oral medications are absorbed, which includes many diabetes drugs. Additionally, chromium and gymnema both lower blood sugar theoretically, so combining them with your diabetes medication raises hypoglycemia risk. Talk to your doctor or pharmacist before starting this product—they may recommend spacing it 30–60 minutes away from your medications.
What are the most common side effects?
Bloating, gas, diarrhea, and abdominal cramping are typical when you first start taking fiber supplements. These usually improve when you start with a small dose and gradually increase it. Make sure you drink plenty of water with each dose—that's key to avoiding blockage and reducing GI upset.
Is Glucomannan+ safe to take if I'm on a blood thinner like warfarin?
No—not without your doctor's input. L-carnitine and chitosan in this product both may increase bleeding risk when taken with warfarin. You'll need to check with your doctor or pharmacist before using this product.
Can I take this if I'm pregnant?
Data for most of these ingredients during pregnancy is limited or insufficient. Guar gum, chromium, and konjac glucomannan carry cautions during pregnancy; gymnema and chitosan should be avoided. Talk with your doctor or pharmacist before using this product if you're pregnant or planning to become pregnant—they can give you personalized guidance based on your health.
Does this product contain shellfish?
The chitosan ingredient (LipoSan Ultra) is derived from shellfish, so if you have a shellfish allergy, you should avoid this product or ask your doctor or pharmacist whether it's safe for you.
How does this product work to support blood sugar?
Through its soluble fibers (guar gum and konjac glucomannan), chromium, and gymnema extract. The fibers slow digestion and sugar absorption; chromium supports how your body uses insulin; and gymnema may help lower blood glucose. The evidence for some of these uses is stronger than others—chromium is possibly effective for diabetes, gymnema's effectiveness isn't well established, and the fibers are possibly effective.

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+ label
Go deeper

The Full Monographs Behind Glucomannan+’s Ingredients

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

Herb & supplement monograph

Guar Gum

Interacts with 2,025 drugs

Guar gum is a soluble, gel-forming fiber from the guar bean that may modestly help with cholesterol, blood sugar, and bowel regularity. It is generally safe in food amounts, but concentrated...

Read the full Guar Gum monograph → Herb & supplement monograph

Chromium

Interacts with 178 drugs

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control in certain people with type 2 diabetes, b...

Read the full Chromium monograph → Herb & supplement monograph

Pectin

Interacts with 23 drugs

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 help with cholesterol, blood sugar, and di...

Read the full Pectin monograph → Herb & supplement monograph

L-carnitine

Interacts with 19 drugs

L-carnitine is a compound your body makes naturally and also gets from foods like meat. It helps cells turn fat into energy, and supplements are most clearly useful for people with a true ca...

Read the full L-carnitine monograph → Herb & supplement monograph

Gymnema

Interacts with 851 drugs

Gymnema is an Ayurvedic herb best known for possibly helping lower blood sugar and reducing the taste of sweetness on the tongue. Some early human studies are encouraging for blood sugar sup...

Read the full Gymnema 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...

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Sources

Sources & How We Checked

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 175 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.

Guar Gum 26 references
  1. Gin H, Orgerie MB, Aubertin J. The influence of Guar gum on absorption of metformin from the gut in healthy volunteers. Horm Metab Res 1989;21:81-3.
  2. Huupponen R, Seppala P, Iisalo E. Effect of guar gum, a fibre preparation, on digoxin and penicillin absorption in man. Eur J Clin Pharmacol 1984;26:279-81. PubMed
  3. Malo JL, Cartier A, L'Archeveque J, et al. Prevalence of occupational asthma and immunologic sensitization to guar gum among employees at a carpet-manufacturing plant. J Allergy Clin Immunol 1990;86:562-9. PubMed
  4. Lagier F, Cartier A, Somer J, et al. Occupational asthma caused by guar gum. J Allergy Clin Immunol 1990;85:785-90.
  5. Lewis JH. Esophageal and small bowel obstruction from guar gum-containing diet pills: analysis of 26 cases reported to the FDA. Am J Gastroenterol 1992;87:1424-8.
  6. Vuorinen-Markkola H, Sinisalo M, Koivisto VA. Guar gum in insulin-dependent diabetes: effects on glycemic control and serum lipoproteins. Am J Clin Nutr 1992;56:1056-1060. PubMed
  7. Superko HR, Haskell WL, Sawrey-Kubicek L, Farquhar JW. Effects of solid and liquid guar gum on plasma cholesterol and triglyceride concentrations in moderate hypercholesterolemia. Am J Cardiol 1988;62:51-5. PubMed
  8. 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
  9. Groop PH, Aro A, Stenman S, Groop L. Long-term effects of guar gum in subjects with non-insulin-dependent diabetes mellitus. Am J Clin Nutr 1993;58:513-8. PubMed
  10. Chuang LM, Jou TS, Yang WS, et al. Therapeutic effect of guar gum in patients with non-insulin-dependent diabetes mellitus. J Formos Med Assoc 1992;91:15-9.
  11. Ebeling P, Yki-Jarvinen H, Aro A, et al. Glucose and lipid metabolism and insulin sensitivity in type 1 diabetes: the effect of guar gum. Am J Clin Nutr 1988;48:98-103. PubMed
  12. Scheen AJ. Clinical pharmacokinetics of metformin. Clin Pharmacokinet 1996;30:359-71. PubMed
  13. Knopp RH, Superko HR, Davidson M, et al. Long-term blood cholesterol-lowering effects of a dietary fiber supplement. Am J Prev Med 1999;17:18-23. PubMed
  14. Patrick PG, Gohman SM, Marx SC, et al. Effect of supplements of partially hydrolyzed guar gum on the occurrence of constipation and use of laxative agents. J Am Diet Assoc 1998;98:912-4. PubMed
  15. Osterlund P, Ruotsalainen T, Korpela R, et al. Lactobacillus supplementation for diarrhoea related to chemotherapy of colorectal cancer: a randomised study. Br J Cancer 2007;97:1028-34. PubMed
  16. Lembcke B, Hasler K, Kramer P, et al. Plasma digoxin concentrations during administration of dietary fibre (guar gum) in man. Z Gastroenterol 1982;20;164-7.
  17. Riikonen, S., Savonius, H., Gylling, H., Nikkila, K., Tuomi, A. M., and Miettinen, T. A. Oral guar gum, a gel-forming dietary fiber relieves pruritus in intrahepatic cholestasis of pregnancy. Acta Obstet.Gynecol.Scand. 2000;79(4):260-264. DOI
  18. Kovacs, E. M., Westerterp-Plantenga, M. S., Saris, W. H., Goossens, I., Geurten, P., and Brouns, F. The effect of addition of modified guar gum to a low-energy semisolid meal on appetite and body weight loss. Int.J.Obes.Relat Metab Disord. 2001;25(3):307 PubMed
  19. Halama, W. H. and Mauldin, J. L. Distal esophageal obstruction due to a guar gum preparation (Cal-Ban 3000). South.Med.J. 1992;85(6):642-645. PubMed
  20. Landin, K., Holm, G., Tengborn, L., and Smith, U. Guar gum improves insulin sensitivity, blood lipids, blood pressure, and fibrinolysis in healthy men. Am.J.Clin.Nutr. 1992;56(6):1061-1065. PubMed
  21. Cicero, A. F., Derosa, G., Manca, M., Bove, M., Borghi, C., and Gaddi, A. V. Different effect of psyllium and guar dietary supplementation on blood pressure control in hypertensive overweight patients: a six-month, randomized clinical trial. Clin.Exp.Hyp PubMed
  22. Simons LA, Gayst S, Balasubramaniam S, Ruys J. Long-term treatment of hypercholesterolaemia with a new palatable formulation of guar gum. Atherosclerosis 1982;45:101-108. PubMed
  23. Salenius JP, Harju E, Jokela H, et al. Long term effects of guar gum on lipid metabolism after carotid endarterectomy. BMJ 1-14-1995;310:95-96. PubMed
  24. Gylling, H., Riikonen, S., Nikkila, K., Savonius, H., and Miettinen, T. A. Oral guar gum treatment of intrahepatic cholestasis and pruritus in pregnant women: effects on serum cholestanol and other non-cholesterol sterols. Eur.J.Clin.Invest 1998;28(5):35 PubMed
  25. Brillantino A, Iacobellis F, Izzo G, et al. Maintenance therapy with partially hydrolyzed guar gum in the conservative treatment of chronic anal fissure: results of a prospective, randomized study. Biomed Res Int 2014;2014:964942. PubMed
  26. Polymeros D, Beintaris I, Gaglia A, et al. Partially hydrolyzed guar gum accelerates colonic transit time and improves symptoms in adults with chronic constipation. Dig Dis Sci 2014;59(9):2207-14. PubMed

See these in context on the Guar Gum monograph →

Chromium 53 references
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  2. Urberg M, Zemel MB. Evidence for synergism between chromium and nicotinic acid in the control of glucose tolerance in elderly humans. Metabolism 1987;36:896-9. PubMed
  3. Mohamedshah FY, Moser-Veillon PB, Yamini S, et al. Distribution of a stable isotope of chromium (53Cr) in serum, urine, and breast milk in lactating women. Am J Clin Nutr 1998;67:1250-5. PubMed
  4. Wasser WG, Feldman NS, D'Agati VD. Chronic renal failure after ingestion of over-the-counter chromium picolinate. [letter]. Ann Intern Med 1997;126:410. PubMed
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  8. Fowler JF Jr. Systemic contact dermatitis caused by oral chromium picolinate. Cutis 2000;65:116. DOI
  9. Trent LK, Thieding-Cancel D. Effects of chromium picolinate on body composition. J Sports Med Phys Fitness 1995;35:273-80.
  10. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  11. Rabinovitz H, Friedensohn A, Leibovitz A, et al. Effect of chromium supplementation on blood glucose and lipid levels in type 2 diabetes mellitus elderly patients. Int J Vitam Nutr Res 2004;74:178-82. PubMed
  12. Lanca S, Alves A, Vieira AI, et al. Chromium-induced toxic hepatitis. Eur J Intern Med 2002;13:518-20. PubMed
  13. Kockler DR, McCarthy MW, Lawson CL. Seizure activity and unresponsiveness after hydroxycut ingestion. Pharmacotherapy 2001;21:647-51.. PubMed
  14. Davidson JR, Abraham K, Connor KM, McLeod MN. Effectiveness of chromium in atypical depression: a placebo-controlled trial. Biol Psychiatry 2003;53:261-4.. PubMed
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  16. Mouser JF, Hak EB, Helms RA, et al. Chromium and zinc concentrations in pediatric patients receiving long-term parenteral nutrition. Am J Health Syst Pharm 1999;56:1950-6. PubMed
  17. Stevens T, Qadri A, Zein NN. Two patients with acute liver injury associated with use of the herbal weight-loss supplement hydroxycut. Ann Intern Med 2005;142:477-8. PubMed
  18. Wani S, Weskamp C, Marple J, Spry L. Acute tubular necrosis associated with chromium picolinate-containing dietary supplement. Ann Pharmacother 2006;40:563-6. PubMed
  19. Kleefstra N, Houweling ST, Jansman FG, et al. Chromium treatment has no effect in patients with poorly controlled, insulin-treated type 2 diabetes in an obese Western population: a randomized, double-blind, placebo-controlled trial. Diabetes Care 2006;29: PubMed
  20. Martin J, Wang ZQ, Zhang XH, et al. Chromium picolinate supplementation attenuates body weight gain and increases insulin sensitivity in subjects with type 2 diabetes. Diabetes Care 2006;29:1826-32. PubMed
  21. Singer GM, Geohas J. The effect of chromium picolinate and biotin supplementation on glycemic control in poorly controlled patients with type 2 diabetes mellitus: a placebo-controlled, double-blinded, randomized trial. Diabetes Technol Ther 2006;8:636-43. PubMed
  22. John-Kalarickal J, Pearlman G, Carlson HE. New medications which decrease levothyroxine absorption. Thyroid 2007;17:763-5. PubMed
  23. Yazaki Y, Faridi Z, Ma Y, et al. A pilot study of chromium picolinate for weight loss. J Altern Complement Med 2010;16:291-9. PubMed
  24. Davis ML, Seaborn CD, and Stoecker BJ. Effects of over-the-counter drugs on chromium retention and urinary excretion in rats. Nutrition Research 1995;15(2):201-210.
  25. Young P, Turiansky G, Bonner M, and et al. Acute generalized exanthematous pustulosis induced by chromium picolinate. J.Am Acad.Dermatol. 1999;41(5 Pt 2):820-823. PubMed
  26. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Lung cancer among workers in chromium chemical production. Am J Ind.Med 2000;38(2):115-126. DOI
  27. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Clinical findings of irritation among chromium chemical production workers. Am J Ind.Med 2000;38(2):127-131. PubMed
  28. Pittler, M. H. and Ernst, E. Dietary supplements for body-weight reduction: a systematic review. Am.J.Clin Nutr. 2004;79(4):529-536. PubMed
  29. Pei, D., Hsieh, C. H., Hung, Y. J., Li, J. C., Lee, C. H., and Kuo, S. W. The influence of chromium chloride-containing milk to glycemic control of patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled trial. Metabolism 2 PubMed
  30. Hisatomi, K., Ishii, H., Hashiguchi, K., Seki, M., Ide, M., Sugiyama, K., Ishimoto, H., Nakayama, S., Mukae, H., and Kohno, S. Interstitial pneumonia caused by inhalation of fumes of nickel and chrome. Respirology. 2006;11(6):814-817. PubMed
  31. Kleefstra, N., Houweling, S. T., Bakker, S. J., Verhoeven, S., Gans, R. O., Meyboom-de Jong, B., and Bilo, H. J. Chromium treatment has no effect in patients with type 2 diabetes in a Western population: a randomized, double-blind, placebo-controlled tri DOI
  32. Parsons, A., Ingram, J., Inglis, J., Aveyard, P., Johnstone, E., Brown, K., Franklin, M., and Bermudez, I. A proof of concept randomised placebo controlled factorial trial to examine the efficacy of St John's wort for smoking cessation and chromium to pr
  33. Bagdon RE and Hazen RE. Skin permeation and cutaneous hypersensitivity as a basis for making risk assessments of chromium as a soil contaminant. Environ.Health Perspect. 1991;92:111-119. PubMed
  34. Bharmal, S. V., Moyes, V., Ahmed, S., and Grossman, A. Hypoglycaemia: possible mediation by chromium salt medication. Hormones.(Athens.) 2010;9(2):181-183. PubMed
  35. Krol, E., Krejpcio, Z., Byks, H., Bogdanski, P., and Pupek-Musialik, D. Effects of chromium brewer's yeast supplementation on body mass, blood carbohydrates, and lipids and minerals in type 2 diabetic patients. Biol.Trace Elem.Res. 2011;143(2):726-737.
  36. Unisa, S., Jagannath, P., Dhir, V., Khandelwal, C., Sarangi, L., and Roy, T. K. Population-based study to estimate prevalence and determine risk factors of gallbladder diseases in the rural Gangetic basin of North India. HPB (Oxford) 2011;13(2):117-125. PubMed
  37. Noda, S., Asano, Y., and Sato, S. Lichen planus in a patient with long-term exposure to chrome. Eur.J.Dermatol. 2011;21(3):417-418. PubMed
  38. Xiang, J., Sun, Z., and Huan, J. N. Intensive chromic acid burns and acute chromium poisoning with acute renal failure. Chin Med.J.(Engl.) 7-5-2011;124(13):2071-2073.
  39. Chhabra, D., Oda, K., Jagannath, P., Utsunomiya, H., Takekoshi, S., and Nimura, Y. Chronic heavy metal exposure and gallbladder cancer risk in India, a comparative study with Japan. Asian Pac.J.Cancer Prev. 2012;13(1):187-190. PubMed
  40. Huszonek, J. Over-the-counter chromium picolinate. Am J Psychiatry 1993;150(10):1560-1561. PubMed
  41. Bunner S and McGinnis R. Chromium-induced hypoglycemia. Psychosomatics 1998;39(3):298-299. PubMed
  42. Martin, W. R. and Fuller, R. E. Suspected chromium picolinate-induced rhabdomyolysis. Pharmacotherapy 1998;18(4):860-862. DOI
  43. Proctor, D. M., Fredrick, M. M., Scott, P. K., Paustenbach, D. J., and Finley, B. L. The prevalence of chromium allergy in the United States and its implications for setting soil cleanup: a cost-effectiveness case study. Regul.Toxicol Pharmacol 1998;28(1 PubMed
  44. De Marchi S, Cecchin E, De Marchi SU. Systemic allergic dermatitis resulting from oral administration of chromium with a food supplement. Contact Dermatitis 2014;70(2):123-5. PubMed
  45. Hedberg YS, Gumulka M, Lind ML, Matura M, Lidén C. Severe occupational chromium allergy despite cement legislation. Contact Dermatitis. 2014;70(5):321-3. PubMed
  46. Thyssen JP, Jellesen MS, Møller P, Menné T, Johansen JD. Allergic chromium dermatitis from wearing 'chromium-free' footwear. Contact Dermatitis 2014;70(3):185-7. PubMed
  47. Liu Y, Cotillard A, Vatier C, et al. A Dietary Supplement Containing Cinnamon, Chromium and Carnosine Decreases Fasting Plasma Glucose and Increases Lean Mass in Overweight or Obese Pre-Diabetic Subjects: A Randomized, Placebo-Controlled Trial. PLoS One.
  48. Jamilian M, Asemi Z. Chromium Supplementation and the Effects on Metabolic Status in Women with Polycystic Ovary Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial. Ann Nutr Metab. 2015;67(1):42-8. PubMed
  49. Guimarães MM, Carvalho AC, Silva MS. Effect of chromium supplementation on the glucose homeostasis and anthropometry of type 2 diabetic patients: Double blind, randomized clinical trial: Chromium, glucose homeostasis and anthropometry. J Trace Elem Med Bi PubMed
  50. Paiva AN, Lima JG, Medeiros AC, et al. Beneficial effects of oral chromium picolinate supplementation on glycemic control in patients with type 2 diabetes: A randomized clinical study. J Trace Elem Med Biol. 2015;32:66-72. PubMed
  51. Yin RV, Phung OJ. Effect of chromium supplementation on glycated hemoglobin and fasting plasma glucose in patients with diabetes mellitus. Nutr J. 2015;14:14. PubMed
  52. Jamilian M, Zadeh Modarres S, Amiri Siavashani M, et al. The influences of chromium supplementation on glycemic control, markers of cardio-metabolic risk, and oxidative stress in infertile polycystic ovary syndrome women candidate for in vitro fertilizati
  53. Alinaghi F, Thyssen JP, Zachariae C, Johansen JD. No immediate effect of regulatory reduction of chromium in leather among adult patients with chromium allergy. Contact Dermatitis 2021;85(5):514-522. PubMed

See these in context on the Chromium 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.
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  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 →

L-carnitine 41 references
  1. Ellaway CM, Williams K, Leonard H, et al. Rett syndrome: randomized controlled trial of L-carnitine. J Child Neurol 1999;14:162-7. PubMed
  2. Anon. Carnitor (levocarnitine) package insert. Sigma-Tau Pharmaceuticals Inc, Gaithersburg, MD. December 1999.
  3. Cherchi A, Lai C, Angelino F, et al. Effects of L-carnitine on exercise tolerance in chronic stable angina: a multicenter, double-blind, randomized, placebo-controlled, crossover study. Int J Clin Pharmacol Ther Toxicol 1985;23:569-72.
  4. Plioplys AV, Plioplys S. Amantadine and L-carnitine treatment of Chronic Fatigue Syndrome. Neuropsychobiology 1997;35:16-23. PubMed
  5. Benvenga S, Ruggeri RM, Russo A, et al. Usefulness of L-carnitine, a naturally occurring peripheral antagonist of thyroid hormone action, in iatrogenic hyperthyroidism: a randomized, double-blind, placebo-controlled clinical trial. J Clin Endocrinol Meta
  6. Martinez E, Domingo P, Roca-Cusachs A. Potentiation of acenocoumarol action by L-carnitine. J Intern Med 1993;233:94.
  7. Bachmann HU, Hoffmann A. Interaction of food supplement L-carnitine with oral anticoagulant acenocoumarol. Swiss Med Wkly 2004;134:385. PubMed
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  11. Cruciani RA, Dvorkin E, Homel P, et al. Safety, tolerability and symptom outcomes associated with L-carnitine supplementation in patients with cancer, fatigue, and carnitine deficiency: a phase I/II study. J Pain Symptom Manage 2006;32:551-9. PubMed
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  13. Malaguarnera M, Cammalleri L, Gargante MP, et al. L-Carnitine treatment reduces severity of physical and mental fatigue and increases cognitive functions in centenarians: a randomized and controlled clinical trial. Am J Clin Nutr 2007;86:1738-44. PubMed
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  15. Angelova-Fischer I, Rippke F, Fischer TW, Neufang G, Zillikens D. A double-blind, randomized, vehicle-controlled efficacy assessment study of a skin care formulation for improvement of mild to moderately severe acne. J Eur Acad Dermatol Venereol. 2013 Jul PubMed
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  18. Van Oudheusden, L. J. and Scholte, H. R. Efficacy of carnitine in the treatment of children with attention-deficit hyperactivity disorder. Prostaglandins Leukot.Essent.Fatty Acids 2002;67(1):33-38. PubMed
  19. Derosa, G., Cicero, A. F., Gaddi, A., Mugellini, A., Ciccarelli, L., and Fogari, R. The effect of L-carnitine on plasma lipoprotein(a) levels in hypercholesterolemic patients with type 2 diabetes mellitus. Clin Ther 2003;25(5):1429-1439. PubMed
  20. Foitzik, K., Hoting, E., Heinrich, U., Tronnier, H., and Paus, R. Indications that topical L-carnitin-L-tartrate promotes human hair growth in vivo. J Dermatol.Sci 2007;48(2):141-144. PubMed
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  22. Cruciani, R. A., Dvorkin, E., Homel, P., Culliney, B., Malamud, S., Lapin, J., Portenoy, R. K., and Esteban-Cruciani, N. L-carnitine supplementation in patients with advanced cancer and carnitine deficiency: a double-blind, placebo-controlled study. J Pa PubMed
  23. Malaguarnera, M., Vacante, M., Avitabile, T., Malaguarnera, M., Cammalleri, L., and Motta, M. L-Carnitine supplementation reduces oxidized LDL cholesterol in patients with diabetes. Am J Clin.Nutr 2009;89(1):71-76. PubMed
  24. Alvarez, T. M., Guardiola, P. D., Roldan, J. O., Elviro, R., Wevers, R., and Guijarro, G. [Primary trimethylaminuria: the fish odor syndrome]. Endocrinol.Nutr. 2009;56(6):337-340.
  25. Wu, Z. M., Lu, X., Wang, Y. W., Sun, J., Tao, J. W., Yin, F. H., and Cheng, H. J. [Short-term medication of L-carnitine before intracytoplasmic sperm injection for infertile men with oligoasthenozoospermia]. Zhonghua Nan.Ke.Xue 2012;18(3):253-256.
  26. Tarighat, Esfanjani A., Mahdavi, R., Ebrahimi, Mameghani M., Talebi, M., Nikniaz, Z., and Safaiyan, A. The effects of magnesium, L-carnitine, and concurrent magnesium-L-carnitine supplementation in migraine prophylaxis. Biol.Trace Elem.Res 2012;150(1-3): PubMed
  27. DiNicolantonio, J. J., Lavie, C. J., Fares, H., Menezes, A. R., and O'Keefe, J. H. L-carnitine in the secondary prevention of cardiovascular disease: systematic review and meta-analysis. Mayo Clin Proc. 2013;88(6):544-551. PubMed
  28. Huang, W. W., Wang, M. Y., Shi, H. M., Peng, Y., Peng, C. S., Zhang, M., Li, Y., Lu, J., and Li, X. B. Comparative study of bioactive constituents in crude and processed Glycyrrhizae radix and their respective metabolic profiles in gastrointestinal tract
  29. Madsen KL, Preisler N, Orngreen MC, Andersen SP, Olesen JH, Lund AM, Vissing J. Patients with medium-chain acyl-coenzyme a dehydrogenase deficiency have impaired oxidation of fat during exercise but no effect of L-carnitine supplementation. J Clin Endocri
  30. Prohaska ES, Muzyk AJ, Rivelli SK. Levocarnitine-induced hypophosphatemia in a hemodialysis patient with acute valproic acid toxicity. J Neuropsychiatry Clin Neurosci. 2012 Winter;24(1):E18-9. PubMed
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  32. Zhang JJ, Wu ZB, Cai YJ, Ke B, Huang YJ, Qiu CP, Yang YB, Shi LY, Qin J. L-carnitine ameliorated fasting-induced fatigue, hunger, and metabolic abnormalities in patients with metabolic syndrome: a randomized controlled study. Nutr J. 2014 Nov 26;13:110. PubMed
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  34. Jun DW, Kim BI, Cho YK, Kim HJ, Kwon YO, Park SY, Han SY, Baek YH, Jung YJ, Kim HY, Kim W, Heo J, Woo HY, Hwang SG, Rim KS, Choi JY, Bae SH, Lee YS, Lim YS,Cheong JY, Cho SW, Lee BS, Kim SH, Sohn JH, Kim TY, Paik YH, Kim JK, Lee KS. Efficacy and safety of
  35. An JH, Kim YJ, Kim KJ, et al. L-carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment: a randomized, double-blind, placebo-controlled trial. Endocr J. 2016;63(10):885-95. PubMed
  36. Chen N, Yang M, Zhou M, Xiao J, Guo J, He L. L-carnitine for cognitive enhancement in people without cognitive impairment. Cochrane Database Syst Rev. 2017;3:CD009374. PubMed
  37. Khajeh B, Dashti-Khavidaki S, Nasiri-Toosi M, Mohammadi K, Jafari A. Effects of pre-transplant L-carnitine supplementation on primary graft dysfunction in liver transplant recipients: a pilot, randomized, placebo-controlled clinical trial. Res Pharm Sci. PubMed
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Gymnema 12 references
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Glucomannan 15 references
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See these in context on the Glucomannan monograph →

Chitosan 17 references
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See these in context on the Chitosan 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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