Major interaction on record — check this product against your medications before combining. Based on 2 of 3 ingredients. Check your meds →
Dietary supplement

Flex RX Ingredients & Drug Interactions

by IronMagLabs

Flex RX label
See full label image
Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Flex RX 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: Major

Flex RX is a dietary supplement by IronMagLabs with 3 active ingredients. Its ingredients are commonly taken for osteoarthritis joint pain, joint stiffness, cartilage support.Based on those ingredients, 170 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Glucosamine Sulfate, Chondroitin Sulfate. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Flex RX by IronMagLabs

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

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HelloPharmacist Scorecard of Flex RX by IronMagLabs

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 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Flex RX contains three active ingredients. Glucosamine sulfate and chondroitin sulfate are compounds believed to support joint structure; chondroitin is a natural component of cartilage, while glucosamine is thought to help cartilage formation.

MSM (methylsulfonylmethane) is also included, though we hold no interaction data for it. The product also contains inactive ingredients — gelatin, vegetable magnesium stearate, and silicon dioxide — which are excipients used to form the capsule and improve flow.

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: joint pain and cartilage support.
  • We looked for evidence on: Joint pain, Knee pain, Osteoarthritis, Back pain, Exercise-induced muscle soreness, Kashin-Beck Disease — and 4 related terms.
  • The strongest evidence on file: Glucosamine is rated "Likely Effective" for Osteoarthritis (Natural Medicines).
  • Also on file: Chondroitin Sulfate is rated "Possibly Effective" for Osteoarthritis.
  • Also on file: Chondroitin Sulfate is rated "Insufficient Reliable Evidence To Rate" for Exercise-induced muscle soreness, Temporomandibular disorders (TMD), Kashin-Beck disease.

Glucosamine sulfate is rated likely effective for osteoarthritis, the main reason people take this product. Chondroitin is rated possibly effective for both osteoarthritis and cataracts.

For other uses listed in the research — aging skin, back pain, liver disease, and colorectal issues — the evidence we hold is insufficient to rate either ingredient. The data on MSM's effectiveness isn't on file for us to review.

The evidence, ingredient by ingredient Chondroitin Sulfate Glucosamine

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

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

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

Both glucosamine and chondroitin are generally well tolerated by most adults when taken by mouth. The most common side effects are digestive: bloating, constipation, cramps, diarrhea, heartburn, and nausea.

Rare serious effects include liver damage (chondroitin) and allergic reactions ranging from mild (itching, hives, lip swelling) to severe (difficulty breathing, anaphylaxis); one review found that 72% of glucosamine-related adverse reports in Australia involved hypersensitivity reactions. Both ingredients have also been linked to asthma flare-ups in rare cases, and chondroitin can cause skin symptoms like rashes and eyelid or limb swelling.

For pregnancy, the safety data advises against both glucosamine and chondroitin — there isn't enough information to know they're safe, so the data recommends avoiding them. For breastfeeding, there isn't enough safety information for either ingredient; talk with your doctor or pharmacist before taking this product if you're nursing.

Side effects, ingredient by ingredient Chondroitin Sulfate Glucosamine

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 2 of the 2 matched ingredients can interact with medications — Chondroitin Sulfate, Glucosamine.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 170 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you start Flex RX, check with your doctor or pharmacist if you take warfarin (Coumadin) or any other blood thinner — glucosamine and chondroitin may increase bleeding risk. Also flag any chemotherapy drugs (especially topoisomerase II inhibitors like etoposide or doxorubicin), diabetes medications, or regular acetaminophen use.

If you take any of these, confirm it's safe to combine with this product.

Check your own medication Run your meds through the checker above

The bottom line

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

Flex RX is primarily used for osteoarthritis, where glucosamine is likely to help and chondroitin possibly will. It's generally well tolerated, but if you take warfarin or any blood thinner, certain chemotherapy drugs, diabetes medications, or acetaminophen regularly, you need to review this with your own doctor or pharmacist before starting — the interactions could be significant.

Avoid it during pregnancy or breastfeeding unless your doctor says otherwise.

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

Assessment coverage: 2 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jul 24, 2015.

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 Flex RX, straight from the product label.

Brand IronMagLabs
Barcode (UPC) 092617188110
Net contents 200 Capsule(s)
Market status On market
Date entered into DSLD Jul 24, 2015
DSLD ID 47370
Product type Non-nutrient/non-botanical
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 Flex RX by IronMagLabs, 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:
5 Capsule(s)
Maximum serving Sizes:
5 Capsule(s)
UPC/BARCODE
092617188110
IngredientAmount% DV
Chondroitin Sulfate1200 mg--
Glucosamine Sulfate1500 mg--
MSM2000 mg--

Other ingredients: Gelatin, Vegetable Magnesium Stearate, Silicon Dioxide

Tap any ingredient to jump to its full detail below.

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

3840-1881-200

Suggested/Recommended/Usage/Directions

Suggested use: Five capsules taken daily with meals as a dietary supplement, or as directed by a health care professional.

Precautions

Caution: Do not exceed recommended dose.

This product is not intended for persons with allergies to shellfish.

Pregnant or nursing mothers, children under 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement.

This product is manufactured and packaged in a facility which may also process milk, soy, wheat, egg, peanuts, tree nuts, fish and crustacean shellfish.

ALLERGEN WARNING: MAY CONTAIN SHELLFISH (GLUCOSAMINE).

Keep out of the reach of children.

Do not use if safety seal is damaged or missing.

Pregnant or nursing mothers, children under 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement.

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

General Statements

Joint builder

Storage

Store in a cool, dry place

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

See for yourself

Flex RX by IronMagLabs label

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

Flex RX 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 Flex RX by IronMagLabs

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size5 Capsule(s) Dosage formCapsule 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.

Chondroitin Sulfate

Interacts with
2 drugs
1200 mg per serving

Chondroitin sulfate is a naturally occurring building block of cartilage that is widely taken, often with glucosamine, for osteoarthritis joint pain....

Chondroitin Sulfate monograph & interactions

Glucosamine Sulfate

Interacts with
170 drugs
1500 mg per serving

Glucosamine is a natural compound found in cartilage and joint fluid, and it is one of the most popular supplements for osteoarthritis, especially of...

Glucosamine Sulfate monograph & interactions

MSM

2000 mg per serving

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

Interaction report

Flex RX by IronMagLabs Drug Interactions

Want to check YOUR meds against Flex RX?

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
170Drugs
2 Major 13 Moderate 155 Minor

Ingredients driving the most interactions

Glucosamine Sulfate 170
Chondroitin Sulfate 2

Individual Drug Interactions

The ingredients in Flex RX interact with 170 drugs. Click any drug to see the details.

2 of the 3 ingredients in Flex RX interact with drugs. Each result below shows which ingredient is responsible. Glucosamine Sulfate Chondroitin Sulfate

Each ingredient & the kinds of drugs it affects

For each ingredient in Flex RX 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.

Glucosamine Sulfate4 drug types · 170 drugs

Warfarin (Coumadin)

Glucosamine might increase the anticoagulant effects of warfarin and increase the risk of bruising and bleeding.
In two individual case reports, glucosamine/chondroitin combinations were associated with a significant increase in international normalized ratio (INR) in patients previously stabilized on warfarin. In one case, the increase in INR occurred only after tripling the dose of a glucosamine/chondroitin supplement from 500 mg/400 mg daily to 1500/1200 mg daily. Additionally, 20 voluntary case reports to the U.S. Food & Drug Administration (FDA) have linked glucosamine plus chondroitin with increased INR, bruising, and bleeding in patients who were also taking warfarin. There have also been 20 additional case reports to the World Health Organization (WHO) that link glucosamine alone to increased INR in patients taking warfarin. The mechanism of this interaction is unclear. Glucosamine is a small component of heparin, but is not thought to have anticoagulant activity; however, animal research suggests that it might have antiplatelet activity.

Likelihood Probable Evidence D
Topoisomerase Ii Inhibitors

Theoretically glucosamine may induce resistance to topoisomerase II inhibitors.
In vitro research suggests that glucosamine might induce resistance to etoposide (VP16, VePesid) and doxorubicin (Adriamycin) by reducing inhibition of topoisomerase II, an enzyme required for DNA replication in tumor cells. This effect has not been reported in humans.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

Acetaminophen might interfere with the activity of glucosamine sulfate by interacting with the sulfate portion.
Anecdotal reports suggest that adding glucosamine to an acetaminophen regimen might decrease pain control in patients with osteoarthritis. Some research suggests that the sulfate portion of glucosamine sulfate might contribute to its effect in osteoarthritis. Since acetaminophen metabolism requires sulfur and reduces serum sulfate concentrations, acetaminophen could theoretically interfere with the action of glucosamine sulfate. Conversely, the administration of sulfate could theoretically decrease the effectiveness of acetaminophen in sulfate-deficient people by increasing its clearance.

Likelihood Possible Evidence B
Antidiabetes Drugs

Despite initial concerns, it is unlikely that glucosamine will interfere with the effects of antidiabetes drugs.
In vitro and animal research has suggested that glucosamine might increase insulin resistance or decrease insulin production. This has raised concerns that taking glucosamine might worsen diabetes and decrease the effectiveness of diabetes drugs. However, clinical research suggests that glucosamine does not have adverse effects on blood glucose or glycated hemoglobin (HbA1C) in healthy, obese, or type 2 diabetes patients.

Likelihood Unlikely Evidence B
Glucosamine Sulfate full monograph & interactions

Chondroitin Sulfate1 drug type · 2 drugs

Warfarin (Coumadin)

Taking chondroitin in combination with glucosamine might increase the anticoagulant effects of warfarin. However, the effect of chondroitin alone is unclear.
There have been multiple reports of increased international normalized ratio (INR) in patients taking warfarin with glucosamine, with or without chondroitin. The lack of reports with chondroitin alone seem to suggest that the interactions occurring in these reports may have been due to glucosamine. In two individual case reports, glucosamine/chondroitin combinations were associated with a significant increase in INR in patients previously stabilized on warfarin. Additionally, 20 voluntary case reports to the US Food & Drug Administration (FDA) have linked glucosamine plus chondroitin with increased INR, bruising, and bleeding in patients who were also taking warfarin. There have also been 20 additional case reports to the World Health Organization (WHO) that link glucosamine alone, without chondroitin, to increased INR in patients taking warfarin.

Likelihood Unlikely Evidence D
Chondroitin Sulfate full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Flex RX, from the product label.

IronMagLabs

See all IronMagLabs products
Name
IronMagLabs
Phone Number
800-815-3350
Web Address
www.ironmaglabs.com
Pharmacist Counseling Corner

Flex RX by IronMagLabs: Common Questions

Does Flex RX by IronMagLabs interact with any medications?
Yes. Based on its ingredients, Flex RX has a known interaction with 170 medications, including 2 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Flex RX contains 3 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 Flex RX if I'm on warfarin?
Not without checking with your doctor first. Glucosamine and chondroitin in this product may increase how thin your blood gets on warfarin and raise your bleeding risk. Case reports show they can significantly change your INR. Talk to your own doctor or pharmacist before starting.
What are the most common side effects?
Digestive upset is most common: bloating, constipation, cramps, diarrhea, heartburn, and nausea. Allergic reactions are rare but can range from mild itching and hives to severe breathing trouble. A few cases of asthma flare-ups and skin rashes have also been reported.
Is Flex RX safe during pregnancy?
No. The safety data for both glucosamine and chondroitin advises against use during pregnancy because there isn't enough information to know they're safe. Talk with your doctor or pharmacist before taking it if you're pregnant or planning to become pregnant.
Is it safe while breastfeeding?
There isn't enough safety information for either glucosamine or chondroitin while breastfeeding. The data recommends avoiding this product unless your doctor advises otherwise. Talk with your healthcare provider about whether it's right for you.
Does glucosamine really help osteoarthritis?
Glucosamine sulfate is rated likely effective for osteoarthritis, so research supports its use for that condition. Chondroitin is rated possibly effective — so it may help, but the evidence is less strong. Results vary from person to person, and benefit can take time to notice.
What's in this product besides the active ingredients?
The capsule is made from gelatin, and the formula includes vegetable magnesium stearate and silicon dioxide as inactive ingredients — these are fillers and binders used to form and stabilize the capsule.

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.

Flex RX label
Go deeper

The Full Monographs Behind Flex RX’s Ingredients

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

Herb & supplement monograph

Chondroitin Sulfate

Interacts with 2 drugs

Chondroitin sulfate is a naturally occurring building block of cartilage that is widely taken, often with glucosamine, for osteoarthritis joint pain. The evidence is mixed—some people report...

Read the full Chondroitin Sulfate monograph → Herb & supplement monograph

Glucosamine

Interacts with 170 drugs

Glucosamine is a natural compound found in cartilage and joint fluid, and it is one of the most popular supplements for osteoarthritis, especially of the knee. The evidence is mixed, with so...

Read the full Glucosamine monograph →
Sources

Sources & How We Checked

Flex RX'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 80 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.

Chondroitin Sulfate 22 references
  1. 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.
  2. Tallia AF, Cardone DA. Asthma exacerbation associated with glucosamine-chondroitin supplement. J Am Board Fam Pract 2002;15:481-4..
  3. Danao-Camara T. Potential side effects of treatment with glucosamine and chondroitin. Arthritis Rheum 2000;43:2853. PubMed
  4. Rozenfeld V, Crain JL, Callahan AK. Possible augmentation of warfarin effect by glucosamine-chondroitin. Am J Health Syst Pharm 2004;61:306-307. PubMed
  5. Clegg DO, Reda DJ, Harris CL, et al. Glucosamine, chondroitin sulfate, and the two in combination for painful knee osteoarthritis. N Engl J Med 2006;354:795-808. DOI
  6. Knudsen J, Sokol GH. Potential glucosamine-warfarin interaction resulting in increased international normalized ratio: Case report and review of the literature and MedWatch database. Pharmacotherapy 2008;28:540-8. PubMed
  7. Yue QY, Strandell J, Myrberg O. Concomitant use of glucosamine potentiates the effect of warfarin. Jan 2006. Drug Safety 29(10):911-1010. DOI
  8. Nordling, J. and van, Ophoven A. Intravesical glycosaminoglycan replenishment with chondroitin sulphate in chronic forms of cystitis. A multi-national, multi-centre, prospective observational clinical trial. Arzneimittelforschung. 2008;58(7):328-335. PubMed
  9. Nickel, J. C., Egerdie, B., Downey, J., Singh, R., Skehan, A., Carr, L., and Irvine-Bird, K. A real-life multicentre clinical practice study to evaluate the efficacy and safety of intravesical chondroitin sulphate for the treatment of interstitial cystit
  10. Oliviero, U., Sorrentino, G. P., De Paola, P., Tranfaglia, E., D'Alessandro, A., Carifi, S., Porfido, F. A., Cerio, R., Grasso, A. M., Policicchio, D., and . Effects of the treatment with matrix on elderly people with chronic articular degeneration. Drug
  11. Crowley, D. C., Lau, F. C., Sharma, P., Evans, M., Guthrie, N., Bagchi, M., Bagchi, D., Dey, D. K., and Raychaudhuri, S. P. Safety and efficacy of undenatured type II collagen in the treatment of osteoarthritis of the knee: a clinical trial. Int.J.Med.Sc PubMed
  12. Nickel, J. C., Egerdie, R. B., Steinhoff, G., Palmer, B., and Hanno, P. A multicenter, randomized, double-blind, parallel group pilot evaluation of the efficacy and safety of intravesical sodium chondroitin sulfate versus vehicle control in patients with
  13. Sawitzke, A. D., Shi, H., Finco, M. F., Dunlop, D. D., Harris, C. L., Singer, N. G., Bradley, J. D., Silver, D., Jackson, C. G., Lane, N. E., Oddis, C. V., Wolfe, F., Lisse, J., Furst, D. E., Bingham, C. O., Reda, D. J., Moskowitz, R. W., Williams, H. J.
  14. Wildi, L. M., Raynauld, J. P., Martel-Pelletier, J., Beaulieu, A., Bessette, L., Morin, F., Abram, F., Dorais, M., and Pelletier, J. P. Chondroitin sulphate reduces both cartilage volume loss and bone marrow lesions in knee osteoarthritis patients starti
  15. Pavelka and et al. Double-blind, dose effect study of oral cs 4 & 6 1200mg, 800mg, 200mg against placebo in the treatment of femorotibial osteoarthritis. Wular Rheumatol Liter 1998;27(suppl 2):63.
  16. Cerda C, Bruguera M, Parés A. Hepatotoxicity associated with glucosamine and chondroitin sulfate in patients with chronic liver disease. World J Gastroenterol 2013;19(32):5381-4. PubMed
  17. von Felden J, Montani M, Kessebohm K, Stickel F. Drug-induced acute liver injury mimicking autoimmune hepatitis after intake of dietary supplements containing glucosamine and chondroitin sulfate. Int J Clin Pharmacol Ther 2013;51(3):219-23. PubMed
  18. Provenza JR, Shinjo SK, Silva JM, Peron CR, Rocha FA. Combined glucosamine and chondroitin sulfate, once or three times daily, provides clinically relevant analgesia in knee osteoarthritis. Clin Rheumatol 2015;34:1455-62. PubMed
  19. Ossendza RA, Grandval P, Chinoune F, Rocher F, Chapel F, Bernardini D. [Acute cholestatic hepatitis due to glucosamine forte]. Gastroenterol Clin Biol. 2007 Apr;31(4):449-50.
  20. Greenlee H, Crew KD, Shao T, Kranwinkel G, Kalinsky K, Maurer M, Brafman L, Insel B, Tsai WY, Hershman DL. Phase II study of glucosamine with chondroitin on aromatase inhibitor-associated joint symptoms in women with breast cancer. Support Care Cancer 201 PubMed
  21. Chu EC, Huang KHK, Cheung G, Ng G, Lin A. Delayed Skin Allergy to Glucosamine Chondroitin Supplement. Cureus 2023;15(3):e36310. PubMed
  22. Lila AM, Alekseeva LI, Baranov AA, et al. Chondroitin sulfate and glucosamine combination in patients with knee and hip osteoarthritis: A long-term observational study in Russia. World J Orthop 2023;14(6):443-457. PubMed

See these in context on the Chondroitin Sulfate monograph →

Glucosamine 58 references
  1. Adams ME. Hype about glucosamine. Lancet 1999;354:353-4. PubMed
  2. Balkan B, Dunning BE. Glucosamine inhibits glucokinase in vitro and produces a glucose-specific impairment of in vivo insulin secretion in rats. Diabetes 1994;43:1173-9. PubMed
  3. Giaccari A, Morviducci L, Zorretta D, et al. In vivo effects of glucosamine on insulin secretion and insulin sensitivity in the rat: possible relevance to the maladaptive responses to chronic hyperglycaemia. Diabetologia 1995;38:518-24. PubMed
  4. Holmang A, Nilsson C, Niklasson M, et al. Induction of insulin resistance by glucosamine reduces blood flow but not interstitial levels of either glucose or insulin. Diabetes 1999;48:106-11. PubMed
  5. Houpt JB, McMillan R, Wein C, Paget-Dellio SD. Effect of glucosamine hydrochloride in the treatment of pain of osteoarthritis of the knee. J Rheumatol 1999;26:2423-30.
  6. Barclay TS, Tsourounis C, McCart GM. Glucosamine. Ann Pharmacother 1998;32:574-9.
  7. Shankar RR, Zhu JS, Baron AD. Glucosamine infusion in rats mimics the beta-cell dysfunction of non-insulin-dependent diabetes mellitus. Metabolism 1998;47:573-7.
  8. Almada A, Harvey P, Platt K. Effects of chronic oral glucosamine sulfate on fasting insulin resistance index (FIRI) in non-diabetic individuals. FASEB J 2000;14:A750.
  9. Reginster JY, Deroisy R, Rovati LC, et al. Long-term effects of glucosamine sulfate on osteoarthritis progression: a randomised, placebo-controlled trial. Lancet 2001;357:251-6.
  10. Does glucosamine increase serum lipid levels and blood pressure? Pharmacist's Letter/Prescriber's Letter 2001;17(11):171115.
  11. 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.
  12. Monauni T, Zenti MG, Cretti A, et al. Effects of glucosamine infusion on insulin secretion and insulin action in humans. Diabetes 2000;49:926-35. PubMed
  13. Pouwels MJ, Jacobs JR, Span PN, et al. Short-term glucosamine infusion does not affect insulin sensitivity in humans. J Clin Endocrinol Metab 2001;86:2099-103. DOI
  14. Yun J, Tomida A, Nagata K, Tsuruo T. Glucose-regulated stresses confer resistance to VP-16 in human cancer cells through a decreased expression of DNA topoisomerase II. Oncol Res 1995;7:583-90.
  15. Pavelka K, Gatterova J, Olejarova M, et al. Glucosamine sulfate use and delay of progression of knee osteoarthritis: A 3-year, randomized, placebo-controlled, double-blind study. Arch Intern Med 2002;162:2113-23. PubMed
  16. Tallia AF, Cardone DA. Asthma exacerbation associated with glucosamine-chondroitin supplement. J Am Board Fam Pract 2002;15:481-4..
  17. Scroggie DA, Albright A, Harris MD. The effect of glucosamine-chondroitin supplementation on glycosylated hemoglobin levels in patients with type 2 diabetes mellitus: a placebo-controlled, double-blinded, randomized clinical trial. Arch Intern Med 2003; PubMed
  18. Hoffer LJ, Kaplan LN, Hamadeh MJ, et al. Sulfate could mediate the therapeutic effect of glucosamine sulfate. Metabolism 2001;50:767-70.. PubMed
  19. Yu JG, Boies SM, Olefsky JM. The effect of oral glucosamine sulfate on insulin sensitivity in human subjects. Diabetes Care 2003;26:1941-2. PubMed
  20. Danao-Camara T. Potential side effects of treatment with glucosamine and chondroitin. Arthritis Rheum 2000;43:2853. PubMed
  21. Guillaume MP, Peretz A. Possible association between glucosamine treatment and renal toxicity: comment on the letter by Danao-Camara. Arthritis Rheum 2001;44:2943-4. PubMed
  22. Rozenfeld V, Crain JL, Callahan AK. Possible augmentation of warfarin effect by glucosamine-chondroitin. Am J Health Syst Pharm 2004;61:306-307. PubMed
  23. Tannis AJ, Barban J, Conquer JA. Effect of glucosamine supplementation on fasting and non-fasting plasma glucose and serum insulin concentrations in healthy individuals. Osteoarthritis Cartilage 2004;12:506-11. PubMed
  24. Bush TM, Rayburn KS, Holloway SW, et al. Adverse interactions between herbal and dietary substances and prescription medications: a clinical survey. Altern Ther Health Med 2007;13:30-5.
  25. Stumpf JL, Lin SW. Effect of glucosamine on glucose control. Ann Pharmacother 2006;40:694-8. PubMed
  26. Pham T, Cornea A, Blick KE, et al. Oral glucosamine in doses used to treat osteoarthritis worsens insulin resistance. Am J Med Sci 2007;333:333-9. PubMed
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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.

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