- N-acetyl D-glucosamine
- 2-acetamido-2-deoxyglucose, acetylglucosamine, Arth-X PlusÂ®, chitosamine, ChitoSeal, Clo-Sur PAD, D-glucosamine, disease modifying drugs for osteoarthritis (DMOAD), enhanced glucosamine sulfate, Flexi-FactorsÂ®, glucosamine chlorohydrate, Glucosamine ComplexÂ®, glucosamine hydrochloride, glucosamine hydroiodide, Glucosamine MegaÂ®, glucosamine N-Acetyl, glucosamine sulfate, glucosamine sulphate, Joint FactorsÂ®, N-acetyl D-glucosamine (NAG, N-A-G), Nutri-JointÂ®, poly-N-acetyl glucosamine (pGlcNAc), Poly-NAG, Syvek Patch, Ultra Maximum Strength Glucosamine SulfateÂ®.
- Glucosamine is a natural compound that is found in healthy cartilage. Glucosamine sulfate is a normal constituent of glycoaminoglycans in cartilage matrix and synovial fluid.
- Available evidence from randomized controlled trials supports the use of glucosamine sulfate in the treatment of osteoarthritis, particularly of the knee. It is believed that the sulfate moiety provides clinical benefit in the synovial fluid by strengthening cartilage and aiding glycosaminoglycan synthesis. If this hypothesis is confirmed, it would mean that only the glucosamine sulfate form is effective and non-sulfated glucosamine forms are not effective.
- Glucosamine is commonly taken in combination with chondroitin, a glycosaminoglycan derived from articular cartilage. Use of complementary therapies, including glucosamine, is common in patients with osteoarthritis, and may allow for reduced doses of non-steroidal anti-inflammatory agents.
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Based on human research, there is good evidence to support the use of glucosamine sulfate in the treatment of mild-to-moderate knee osteoarthritis. Most studies have used glucosamine sulfate supplied by one European manufacturer (Rotta Research Laboratorium), and it is not known if glucosamine preparations made by other manufacturers are equally effective.
Although some studies of glucosamine have not found benefits, these have either included patients with severe osteoarthritis or used products other than glucosamine sulfate. The evidence for the effect of glycosaminoglycan polysulphate is conflicting and merits further investigation. More well-designed clinical trials are needed to confirm safety and effectiveness, and to test different formulations of glucosamine.
Several human studies and animal experiments report benefits of glucosamine in treating osteoarthritis of various joints of the body, although the evidence is less plentiful than that for knee osteoarthritis. Some of these benefits include pain relief, possibly due to an anti-inflammatory effect of glucosamine, and improved joint function. Overall, these studies have not been well designed. Although there is some promising research, more study is needed in this area before a firm conclusion can be made.
“Chronic venous insufficiency” is a syndrome that includes leg swelling, varicose veins, pain, itching, skin changes, and skin ulcers. The term is more commonly used in Europe than in the United States. Currently, there is not enough reliable scientific evidence to recommend glucosamine in the treatment of this condition.
Early research suggests that glucosamine does not improve blood sugar control, lipid levels, or apolipoprotein levels in diabetics. Additional research is needed in this area.
Preliminary research reports improvements with N-acetyl glucosamine as an added therapy in inflammatory bowel disease. Further scientific evidence is necessary before a strong recommendation can be made.
Preliminary human research reports benefits of injected glucosamine plus chondroitin in the treatment of leg pain arising from advanced lumbar degenerative disc disease. Further scientific evidence is necessary before a firm recommendation can be made.
Glucosamine has been given to athletes with acute knee injuries. Although glucosamine did not improve pain, it did help improve flexibility. Additional research is needed to confirm these early findings.
Early human research reports benefits of glucosamine in the treatment of joint pain and swelling in rheumatoid arthritis. In other research, glucosamine did not exert anti-rheumatic effects, but it did improve symptoms of the disease. However, this is early information, and additional research is needed before a conclusion can be drawn. The treatment of rheumatoid arthritis can be complicated, and a qualified healthcare provider should follow patients with this disease.
There is a lack of sufficient evidence to recommend for or against the use of glucosamine (or the combination of glucosamine and chondroitin) in the treatment of temporomandibular joint disorders.
Glucosamine does not appear to alter LDL or HDL levels in patients with chronic joint pain or diabetes.
*Key to grades:
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.
Adults (18 years and older)
- In most available studies, 500 milligrams of glucosamine sulfate has been taken by mouth as tablets or capsules three times daily for 30 to 90 days. Once daily dosing as 1.5 grams (1,500 milligrams) has also been used. Limited research has used 1,500 milligrams daily as a crystalline powder for oral solution or 500 milligrams of glucosamine hydrochloride three times daily. Dosing of 20 milligrams per kilogram of body weight daily has also been recommended in some publications. One study used a dose of 2,000 milligrams per day for 12 weeks.
- Another kind of glucosamine that has been used is a topical form in combination with chondroitin for a four-week period. Safety and effectiveness of these formulations are not clearly proven.
- Glucosamine hydrochloride provides more glucosamine than glucosamine sulfate, although this difference likely does not matter when products are prepared to provide a total of 500 milligrams of glucosamine per tablet.
Children (younger than 18 years)
- There is not enough scientific evidence to recommend the use of glucosamine in children.
- Research in children has shown that there could be a relationship between the ingestion of MSM (methylsulfonylmethane) and autism; whether it is beneficial or harmful is unclear. MSM is often marketed with glucosamine as a dietary supplement and at this time should be avoided in children.
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
- Since glucosamine can be made from the shells of shrimp, crab, and other shellfish, people with shellfish allergy or iodine hypersensitivity may have an allergic reaction to glucosamine products. However, some research suggests that there is not enough shrimp allergen in glucosamine supplements to trigger reactions in patients who are allergic to shrimp. Nevertheless, caution is warranted. A serious hypersensitivity reaction including throat swelling has been reported with glucosamine sulfate. There are reported cases suggesting a link between glucosamine/chondroitin products and asthma exacerbations.
Side Effects and Warnings
- In most human studies, glucosamine sulfate has been well tolerated for 30 to 90 days.
- Side effects may include upset stomach, drowsiness, insomnia, headache, skin reactions, sun sensitivity, and nail toughening. There are rare reports of abdominal pain, loss of appetite, vomiting, nausea, flatulence (gas), constipation, heartburn, and diarrhea. Based on several human cases, temporary increases in blood pressure and heart rate, as well as palpitations, may occur with glucosamine/chondroitin products. Based on animal research, glucosamine theoretically may increase the risk for eye cataract formation.
- It remains unclear if glucosamine alters blood sugar levels. Several human studies suggest that glucosamine taken by mouth has no effects on blood sugar, while other research reports mixed effects on insulin. When glucosamine is injected, it appears to cause insulin resistance and endothelial dysfunction. Preliminary studies show no effect on mean hemoglobin A1c concentrations in patients with type 2 diabetes mellitus. Caution is advised in patients with diabetes or hypoglycemia and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a healthcare provider and medication adjustments may be necessary.
- In theory glucosamine may increase the risk of bleeding. Caution is advised in patients with bleeding disorders or taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.
- In several human cases, abnormally high amounts of protein were found in the urine of patients receiving glucosamine/chondroitin products. The clinical meaning of this is unclear. Glucosamine is removed from the body mainly in the urine, and elimination of glucosamine from the body is delayed in people with reduced kidney function. Acute interstitial nephritis, a condition that causes the kidneys to become swollen and possibly dysfunctional, has been reported in a patient taking glucosamine. Increased blood levels of creatine phosphokinase may occur with glucosamine/chondroitin, which may be due to impurities in some products. This may alter certain laboratory tests measured by healthcare providers.
- Early data suggest that glucosamine may modulate the immune system, although the clinical relevance of this is not clear.
- One patient developed liver inflammation (acute cholestatic hepatitis) after taking glucosamine forte.
Pregnancy and Breastfeeding
- Glucosamine is not recommended during pregnancy or breastfeeding due to lack of scientific evidence.
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Interactions with Drugs
- In theory, glucosamine may decrease the effectiveness of insulin or other drugs used to control blood sugar levels. However, there is limited human research to suggest that glucosamine may not have significant effects on blood sugar. Nonetheless, caution is advised when using insulin or drugs for diabetes by mouth. Patients with diabetes or hypoglycemia should be monitored closely by a qualified healthcare provider, and medication adjustments may be necessary. Based on limited evidence, the combination of glucosamine with diuretics (water pills), such as furosemide (LasixÂ®), may cause an increased risk of glucosamine side effects.
- In theory, glucosamine may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (“blood thinners”) such as warfarin (CoumadinÂ®) or heparin, anti-platelet drugs such as clopidogrel (PlavixÂ®), and non-steroidal anti-inflammatory drugs such as ibuprofen (MotrinÂ®, AdvilÂ®) or naproxen (NaprosynÂ®, AleveÂ®).
Interactions with Herbs and Dietary Supplements
- In theory, glucosamine may decrease the effectiveness of herbs or supplements that lower blood sugar levels. Caution is advised when using herbs or supplements that may alter blood sugar.
- Based on limited human study, side effects of glucosamine may be increased when used at the same time as diuretic herbs or supplements.
- In theory, glucosamine may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding
- There are preliminary reports that use of glucosamine with vitamin C, bromelain, chondroitin sulfate, or manganese may lead to increased beneficial glucosamine effects on osteoarthritis. Simultaneous use with fish oil may have additive beneficial effects in the treatment of psoriasis, based on preliminary research.
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
- This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration ().
- Albert SG, Oiknine RF, Parseghian S, et al. The effect of glucosamine on Serum HDL cholesterol and apolipoprotein AI levels in people with diabetes. Diabetes Care 2007 Nov;30(11):2800-3.
- Audimoolam VK, Bhandari S. Acute interstitial nephritis induced by glucosamine. Nephrol Dial Transplant 2006 Jul;21(7):2031.
- 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 Feb 23;354(8):795-808.
- Dudek A, Raczkiewicz-Papierska A, TÅ‚ustochowicz W. [Efficacy of glucosamine sulfate treatment in patients with osteoarthritis] Pol Merkur Lekarski 2007 Mar;22(129):204-7.
- Herrero-Beaumont G, Ivorra JA, Del Carmen Trabado M, et al. Glucosamine sulfate in the treatment of knee osteoarthritis symptoms: a randomized, double-blind, placebo-controlled study using acetaminophen as a side comparator. Arthritis Rheum 2007 Feb;56(2):555-67.
- Mehta K, Gala J, Bhasale S, et al. Comparison of glucosamine sulfate and a polyherbal supplement for the relief of osteoarthritis of the knee: a randomized controlled trial [ISRCTN25438351]. BMC Complement Altern Med 2007 Oct 31;7:34.
- Miller MR, Mathews RS, Reeves KD. Treatment of painful advanced internal lumbar disc derangement with intradiscal injection of hypertonic dextrose. Pain Physician 2006 Apr;9(2):115-21.
- Muniyappa R, Karne RJ, Hall G, et al. Oral glucosamine for 6 weeks at standard doses does not cause or worsen insulin resistance or endothelial dysfunction in lean or obese subjects. Diabetes 2006 Nov;55(11):3142-50.
- Nakamura H, Masuko K, Yudoh K, et al. Effects of glucosamine administration on patients with rheumatoid arthritis. Rheumatol Int 2007 Jan;27(3):213-8.
- Ossendza RA, Grandval P, Chinoune F, et al. [Acute cholestatic hepatitis due to glucosamine forte]. Gastroenterol Clin Biol 2007 Apr;31(4):449-50
- Ã˜stergaard K, Hviid T, Hyllested-Winge JL. [The effect of glucosamine sulphate on the blood levels of cholesterol or triglycerides–a clinical study]. Ugeskr Laeger 2007 Jan 29;169(5):407-10.
- Ostojic SM, Arsic M, Prodanovic S, et al. Glucosamine administration in athletes: effects on recovery of acute knee injury.Res Sports Med 2007 Apr-Jun;15(2):113-24.
- Theodosakis J. A randomized, double blind, placebo controlled trial of a topical cream containing glucosamine sulfate, chondroitin sulfate, and camphor for osteoarthritis of the knee. J Rheumatol 2004;31(4):826-827.
- Thie NM, Prasad NG, Major PW. Evaluation of glucosamine sulfate compared to ibuprofen for the treatment of temporomandibular joint osteoarthritis: a randomized double blind controlled 3 month clinical trial. J Rheumatol 2001;28(6):1347-1355.
- Villacis J, Rice TR, Bucci LR, et al. Do shrimp-allergic individuals tolerate shrimp-derived glucosamine? Clin Exp Allergy 2006 Nov;36(11):1457-61.
Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to . Selected references are listed below.