Glucosamine is a chemical found in the body. Glucosamine supplements are sold as glucosamine sulfate, glucosamine hydrochloride, and N-acetyl glucosamine.

Glucosamine is used by the body to make other chemicals that build tendons, ligaments, cartilage, and the fluid that surrounds joints. Joints are cushioned by the fluid and cartilage around them. Taking glucosamine might increase the cartilage and fluid around joints and/or help prevent their breakdown.

People commonly use glucosamine sulfate and glucosamine hydrochloride for osteoarthritis. Glucosamine is also used for joint pain, rheumatoid arthritis, multiple sclerosis, and many other conditions, but there is no good scientific evidence to support these other uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

The effectiveness ratings for GLUCOSAMINE are as follows:

Likely effective for…

• Osteoarthritis. Taking glucosamine sulfate by mouth for at least 4 weeks can provide some pain relief and improve function for people with knee osteoarthritis. Products that contain glucosamine hydrochloride do not seem to work as well unless they are taken in combination with other ingredients. Taking glucosamine sulfate doesn’t seem to reduce the risk of getting osteoarthritis.

There is interest in using glucosamine for a number of other purposes, but there isn’t enough reliable information to say whether it might be helpful.

When taken by mouth: Glucosamine sulfate is likely safe in most adults when used for up to 3 years. Glucosamine hydrochloride is possibly safe for most adults when used for up to 2 years. N-acetyl glucosamine is also possibly safe when used for up to 6 months. Glucosamine can cause some mild side effects including bloating, nausea, diarrhea, and constipation.

When applied to the skin: N-acetyl glucosamine is possibly safe when used for up to 10 weeks.

When given as an enema (rectally): N-acetyl glucosamine is possibly safe when used in doses of 3-4 grams daily.

Special precautions & warnings:

Pregnancy and breast-feeding: There isn’t enough reliable information to know if glucosamine sulfate, glucosamine hydrochloride, or N-acetyl glucosamine is safe to use when pregnant or breast-feeding. Stay on the safe side and avoid use.

Asthma: Glucosamine might make asthma worse. Until more is known, people with asthma should be cautious about taking products that contain glucosamine.

Diabetes: There used to be some concern that glucosamine might increase blood sugar levels. But most research shows that glucosamine doesn’t increase blood sugar levels in people with diabetes.

Glaucoma: Glucosamine might increase the pressure inside the eye and could worsen glaucoma. If you have glaucoma, talk to your healthcare provider before taking glucosamine.

High cholesterol: There used to be some concern that glucosamine might increase cholesterol levels. But most research shows that glucosamine doesn’t seem to increase cholesterol levels.

High blood pressure: There used to be some concern that glucosamine might increase blood pressure. But most research shows that glucosamine does not seem to increase blood pressure.

Shellfish allergy: Glucosamine is produced from the shells of shrimp, lobster, and crabs. If you have a shellfish allergy, talk to your healthcare provider before using glucosamine.

Major

Do not take this combination.

Warfarin (Coumadin)

Warfarin is used to slow blood clotting. Taking glucosamine with or without chondroitin increases the effects of warfarin. This can increase the risk for serious bruising and bleeding. Don’t take glucosamine if you are taking warfarin.

Moderate

Be cautious with this combination.

Medications for cancer (Topoisomerase II Inhibitors)

Some medications for cancer work by decreasing how fast cancer cells can copy themselves. Glucosamine might block these medications from working. Taking glucosamine along with some medications for cancer might decrease the effectiveness of these medications.

Minor

Be watchful with this combination.

Acetaminophen (Tylenol, others)

Taking glucosamine SULFATE and acetaminophen together might affect how well each works. But more information is needed to know if this interaction is a big concern.

Medications for diabetes (Antidiabetes drugs)

Glucosamine might increase blood sugar levels. Taking glucosamine along with diabetes medications might reduce the effects of these medications. Monitor your blood sugar closely.

Chondroitin sulfate

Taking chondroitin sulfate together with glucosamine HYDROCHLORIDE might reduce blood levels of glucosamine hydrochloride. But it’s not clear if this will change the effects of glucosamine hydrochloride.

There are no known interactions with foods.

Glucosamine sulfate and glucosamine hydrochloride have most often been used by adults in doses of 1500 mg by mouth daily for up to 3 years. Speak with a healthcare provider to find out what dose might be best for a specific condition.

Keep in mind that glucosamine used in supplements often comes from the shells of shellfish. Talk to your healthcare provider before taking these supplements if you have a shellfish allergy. Also, some glucosamine products aren’t labeled correctly. In some cases, the amount of glucosamine actually in the product has varied from none to over 100% of the amount stated on the product’s label. Some products have contained glucosamine hydrochloride when glucosamine sulfate was listed on the label.

(3R,4R,5S,6R)-3-Amino-6-(Hydroxymethyl)Oxane-2,4,5-Triol Hydrochloride, 2-Acetamido-2-deoxyglucose, 2-Amino-2-Deoxy-D-Glucosehydrochloride, 2-Amino-2-Deoxy-Beta-D-Glucopyranose Hydrochloride, 2-Amino-2-Deoxy-Glucose, 2-Amino-2-Deoxy-Beta-D-Glucopyranose, 2-Amino-2-Deoxy-D-Glucose Sulfate, 3-Amino-6-(Hydroxymethyl)Oxane-2,4,5-Triol Sulfate, Acetylglucosamine, Acétylglucosamine, Amino Monosaccharide, Chitosamine, Chitosamine Hydrochloride, Chlorhidrato de Glucosamina, Chlorhydrate de Glucosamine, Chlorure de Potassium-Sulfate de Glucosamine, D-Glucosamine, D-Glucosamine HCl, D-Glucosamine Hydrochloride, D-Glucosamine Sulfate, D-Glucosamine Sulphate, G6S, GlcNAc, Glucosamine HCl, Glucosamine KCl, Glucosamine N-Acetyl, Glucosamine, Glucosamine Potassium Sulfate, Glucosamine Sulphate, Glucosamine Sulfate 2KCl, Glucosamine Sulfate-Potassium Chloride, Glucosamine Sulphate KCl, Glucosamine-6-Phosphate, GS, Mono-Sulfated Saccharide, N-Acetil Glucosamina, N-Acétyl Glucosamine, N-Acétyl-Glucosamine, N-Acétylglucosamine, N-Acetyl D-Glucosamine, N-Acétyl D-Glucosamine, NAG, N-A-G, pGlcNAc, Poly-N-Acetyl Glucosamine, Poly-NAG, Poly-(1->3)-N-Acetyl-2-Amino-2-Deoxy-3-O-Beta-D-Glucopyranurosyl-4-(or 6-) Sul, p-GlcNAc, Saccharide Mono-Sulfaté, Saccharide Sulfaté, Sulfate de Glucosamine, Sulfate de Glucosamine 2KCl, SG, Sulfated Monosaccharide, Sulfated Saccharide, Sulfato de Glucosamina.

To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.

1. Kantor ED, O’Connell K, Liang PS, Navarro SL, Giovannucci EL, Du M. Glucosamine Use and Risk of Colorectal Cancer: Results from UK Biobank. Cancer Epidemiol Biomarkers Prev 2022;31:647-653. View abstract.
2. Zhang J, Ge R, Yang Z. Effect of celecoxib combined with glucosamine hydrochloride in promoting the functional recovery and decreasing the inflammatory factor levels in patients with knee osteoarthritis. Pak J Pharm Sci. 2021;34(3(Special)):1277-82. View abstract.
3. Moon JM, Finnegan P, Stecker RA, et al. Impact of glucosamine supplementation on gut health. Nutrients. 2021;13:2180. View abstract.
4. King DE, Xiang J. Glucosamine/Chondroitin and Mortality in a US NHANES Cohort. J Am Board Fam Med. 2020;33:842-847. View abstract.
5. Lee DH, Cao C, Zong X, et al. Glucosamine and Chondroitin Supplements and Risk of Colorectal Adenoma and Serrated Polyp. Cancer Epidemiol Biomarkers Prev. 2020;29:2693-2701. View abstract.
6. Kumar PNS, Sharma A, Andrade C. A pilot, open-label investigation of the efficacy of glucosamine for the treatment of major depression. Asian J Psychiatr. 2020;52:102113. View abstract.
7. Ma H, Li X, Zhou T, et al. Glucosamine use, inflammation, and genetic susceptibility, and incidence of type 2 diabetes: a prospective study in UK Biobank. Diabetes Care. 2020;43:719-25. View abstract.
8. Bruyere O, Honvo G, Veronese N, et al. An updated algorithm recommendation for the management of knee osteoarthritis from the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis, and Musculoskeletal Disease (ESCEO). Semin Arthritis Rheum. 2019 Dec;49:337-50. View abstract.
9. Navarro SL, Levy L, Curtis KR, Lampe JW, Hullar MAJ. Modulation of Gut Microbiota by Glucosamine and Chondroitin in a Randomized, Double-Blind Pilot Trial in Humans. Microorganisms. 2019 Nov 23;7. pii: E610. View abstract.
10. Restaino OF, Finamore R, Stellavato A, et al. European chondroitin sulfate and glucosamine food supplements: A systematic quality and quantity assessment compared to pharmaceuticals. Carbohydr Polym. 2019 Oct 15;222:114984. View abstract.
11. Hoban C, Byard R, Musgrave I. Hypersensitive adverse drug reactions to glucosamine and chondroitin preparations in Australia between 2000 and 2011. Postgrad Med J. 2019 Oct 9. pii: postgradmedj-2019-136957. View abstract.
12. Kolasinski SL, Neogi T, Hochberg MC, et al. 2019 American College of Rheumatology/Arthritis Foundation guideline for the management of osteoarthritis of the hand, hip, and knee. Arthritis Rheumatol. 2020 Feb;72:220-33. View abstract.
13. Tsuruta A, Horiike T, Yoshimura M, Nagaoka I. Evaluation of the effect of the administration of a glucosamine containing supplement on biomarkers for cartilage metabolism in soccer players: A randomized double blind placebo controlled study. Mol Med Rep. 2018 Oct;18:3941-3948. Epub 2018 Aug 17. View abstract.
14. Simental-Mendía M, Sánchez-García A, Vilchez-Cavazos F, Acosta-Olivo CA, Peña-Martínez VM, Simental-Mendía LE. Effect of glucosamine and chondroitin sulfate in symptomatic knee osteoarthritis: a systematic review and meta-analysis of randomized placebo-controlled trials. Rheumatol Int. 2018 Aug;38:1413-1428. Epub 2018 Jun 11. Review. View abstract.
15. Gregori D, Giacovelli G, Minto C, et al. Association of Pharmacological Treatments with Long-term Pain Control in Patients With Knee Osteoarthritis: A Systematic Review and Meta-analysis. JAMA. 2018 Dec 25;320:2564-2579. View abstract.
16. Ogata T, Ideno Y, Akai M, et al. Effects of glucosamine in patients with osteoarthritis of the knee: a systematic review and meta-analysis. Clin Rheumatol. 2018 Sep;37:2479-2487. Epub 2018 Apr 30. View abstract.
17. Ma H, Li X, Sun D, et al. Association of habitual glucosamine use with risk of cardiovascular disease: prospective study in UK Biobank. BMJ. 2019 May 14;365:l1628. View abstract.
18. de Vos BC, Landsmeer MLA, van Middelkoop M, et al. Long-term effects of a lifestyle intervention and oral glucosamine sulphate in primary care on incident knee OA in overweight women. Rheumatology (Oxford). 2017;56:1326-1334. View abstract.
19. Tsuji T, Yoon J, Kitano N, Okura T, Tanaka K. Effects of N-acetyl glucosamine and chondroitin sulfate supplementation on knee pain and self-reported knee function in middle-aged and older Japanese adults: a randomized, double-blind, placebo-controlled trial. Aging Clin Exp Res. 2016;28:197-205. View abstract.
20. Runhaar J, Deroisy R, van Middelkoop M, et al. The role of diet and exercise and of glucosamine sulfate in the prevention of knee osteoarthritis: Further results from the PRevention of knee Osteoarthritis in Overweight Females (PROOF) study. Semin Arthritis Rheum. 2016;45(4 Suppl):S42-8. View abstract.
21. Roman-Blas JA, Castañeda S, Sánchez-Pernaute O, et al. Combined Treatment With Chondroitin Sulfate and Glucosamine Sulfate Shows No Superiority Over Placebo for Reduction of Joint Pain and Functional Impairment in Patients With Knee Osteoarthritis: A Six-Month Multicenter, Randomized, Double-Blind, Placebo-Controlled Clinical Trial. Arthritis Rheumatol. 2017;69:77-85. View abstract.
22. Kongtharvonskul J, Anothaisintawee T, McEvoy M, Attia J, Woratanarat P, Thakkinstian A. Efficacy and safety of glucosamine, diacerein, and NSAIDs in osteoarthritis knee: a systematic review and network meta-analysis. Eur J Med Res. 2015;20:24. View abstract.
23. Kanzaki N, Ono Y, Shibata H, Moritani T. Glucosamine-containing supplement improves locomotor functions in subjects with knee pain: a randomized, double-blind, placebo-controlled study. Clin Interv Aging. 2015;10:1743-53. View abstract.
24. Gueniche A, Castiel-Higounenc I. Efficacy of Glucosamine Sulphate in Skin Ageing: Results from an ex vivo Anti-Ageing Model and a Clinical Trial. Skin Pharmacol Physiol. 2017;30:36-41. View abstract.
25. Eraslan A, Ulkar B. Glucosamine supplementation after anterior cruciate ligament reconstruction in athletes: a randomized placebo-controlled trial. Res Sports Med. 2015;23:14-26. View abstract.
26. Esfandiari H, Pakravan M, Zakeri Z, et al. Effect of glucosamine on intraocular pressure: a randomized clinical trial. Eye. 2017;31:389-394.
27. Murphy RK, Jaccoma EH, Rice RD, Ketzler L. Glucosamine as a Possible Risk Factor for Glaucoma. Invest Ophthalmol Vis Sci 2009;50:5850.
28. Eriksen P, Bartels EM, Altman RD, Bliddal H, Juhl C, Christensen R. Risk of bias and brand explain the observed inconsistency in trials on glucosamine for symptomatic relief of osteoarthritis: a meta-analysis of placebo-controlled trials. Arthritis Care Res (Hoboken). 2014;66:1844-55. View abstract.
29. Singh JA, Noorbaloochi S, MacDonald R, Maxwell LJ. Chondroitin for osteoarthritis. Cochrane Database Syst Rev. 2015 Jan 28;1:CD005614. View abstract.
30. Bruyère O, Cooper C, Pelletier JP, et al. A consensus statement on the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO) algorithm for the management of knee osteoarthritis-From evidence-based medicine to the real-life setting. Semin
    Arthritis Rheum. 2016;45(4 Suppl):S3-11.
    View abstract.
31. Kimball AB, Kaczvinsky JR, Li J, et al. Reduction in the appearance of facial hyperpigmentation after use of moisturizers with a combination of topical niacinamide and N-acetyl glucosamine: results of a randomized, double-blind, vehicle-controlled trial. Br J Dermatol 2010;162:435-41. View abstract.
32. Madhu K, Chanda K, Saji MJ. Safety and efficacy of Curcuma longa extract in the treatment of painful knee osteoarthritis: a randomized placebo-controlled trial. Inflammopharmacology 2013;21:129-36. View abstract.
33. Vetter G. [Topical therapy of arthroses with glucosamines (Dona 200)]. Munch Med Wochenschr 1969;111:1499-502. View abstract.
34. Setnikar I, Giacchetti C, Zanolo G. Pharmacokinetics of glucosamine in the dog and in man. Arzneimittelforschung 1986;36:729-35. View abstract.
35. Basak M, Joseph S, Joshi S, Sawant S. Comparative bioavailability of a novel timed release and powder-filled glucosamine sulfate formulation–a multi-dose, randomized, crossover study. Int J Clin Pharmacol Ther 2004;42:597-601. View abstract.
36. Phitak T, Pothacharoen P, Kongtawelert P. Comparison of glucose derivatives effects on cartilage degradation. BMC Musculoskelet Disord 2010;11:162. View abstract.
37. Setnikar I, Cereda R, Pacini MA, Revel L. Antireactive properties of glucosamine sulfate. Arzneimittelforschung 1991;41:157-61. View abstract.
38. Sumantran VN, Chandwaskar R, Joshi AK, Boddul S, Patwardhan B, Chopra A, Wagh UV. The relationship between chondroprotective and antiinflammatory effects of Withania somnifera root and glucosamine sulphate on human osteoarthritic cartilage in vitro. Phytother Res 2008;22:1342-8. View abstract.
39. Setnikar I, Pacini MA, Revel L. Antiarthritic effects of glucosamine sulfate studied in animal models. Arzneimittelforschung 1991;41:542-5. View abstract.
40. Bassleer C, Henrotin Y, Franchimont P. In-vitro evaluation of drugs proposed as chondroprotective agents. Int J Tissue React 1992;14:231-41. View abstract.
41. Calamia V, Ruiz-Romero C, Rocha B, Fernández-Puente P, Mateos J, Montell E, Vergés J, Blanco FJ. Pharmacoproteomic study of the effects of chondroitin and glucosamine sulfate on human articular chondrocytes. Arthritis Res Ther 2010;12:R138. View abstract.
42. Graeser AC, Giller K, Wiegand H, Barella L, Boesch Saadatmandi C, Rimbach G. Synergistic chondroprotective effect of alpha-tocopherol, ascorbic acid, and selenium as well as glucosamine and chondroitin on oxidant induced cell death and inhibi