Glucosamine, which occurs naturally in the body, plays a key role in the construction of cartilage, or the tough connective tissue that cushions the joints. Glucosamine stimulates the production of glycosaminoglycans (the key structural components of cartilage) as well as the incorporation of sulfur into cartilage. Sulfur is necessary for making and repairing cartilage.
Clinical studies report that glucosamine may be effective in treating and possibly slowing the progression of osteoarthritis. This is a type of arthritis caused by continuous wear and tear on the joints leading to inflammation, breakdown, and eventual loss of cartilage. The tissues most affected by osteoarthritis are the weight bearing joints, such as the knees and hips, as well as the joints in the hands.
Studies suggest that glucosamine may be at least as effective as some of the medications frequently used to treat this joint condition, but with fewer gastrointestinal side effects. The medications used to treat osteoarthritis are known as nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and piroxicam. NSAIDs may cause stomach upset, cramps, constipation, diarrhea, and in some cases, stomach ulcers.
Glucosamine is often taken with chondroitin, another supplement thought to be effective in treating arthritis. These substances are often combined with manganese as well, a trace metal that is also needed for building cartilage.
Although not every clinical study agrees, strong evidence from many well-designed human trials indicates that glucosamine sulfate supplements may be an effective treatment for osteoarthritis (particularly osteoarthritis of the knees). In general, findings from these clinical studies suggest that glucosamine provides several benefits for people with osteoarthritis including pain reduction (as effective as ibuprofen and other non-steroidal anti-inflammatory drugs or NSAIDs), improved function and mobility, and slowed progression or even prevention of joint destruction when taken for 3 or more years.
In comparison to NSAIDs, glucosamine takes longer to begin working. However, pain control lasts longer with glucosamine and the supplements cause fewer side effects.
Although glucosamine and chondroitin are often administered together for the treatment of osteoarthritis, it is not clear that the combination works better than either supplement alone. Nor is it clear if glucosamine is better than chondroitin or vice versa.
A large clinical study, called the Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) studied the effects of glucosamine/chondroitin combination, celecoxib (Celebrex), and placebo in over 1,500 patients with arthritis in the knees. Overall, glucosamine and chondroitin sulfate were not significantly better than placebo in reducing knee pain by 20%. Glucosamine and chondroitin sulfate alone or in combination did not reduce pain effectively in the overall group of patients with osteoarthritis of the knee, but did help those with moderate-to-severe pain. Although glucosamine is one of the top selling dietary supplements and used by millions, more clinical studies are needed.
Inflammatory bowel disease (IBD)
Crohn's disease and ulcerative colitis are two inflammatory bowel diseases that are marked by chronic, recurrent bloody diarrhea. Preliminary clinical evidence suggests that N-acetyl glucosamine oral supplements or enemas may improve symptoms of IBD in children who do not improve from standard medical treatments. Further research is needed, however, to determine whether the substance is safe and effective for the treatment of IBD.
There are no food sources of glucosamine. Most supplements are derived from chitin, the hard outer shells of shrimp, lobsters, and crabs. Other forms of glucosamine are available for individuals who are allergic to shellfish.
Glucosamine is available in oral supplements as glucosamine sulfate, glucosamine hydrochloride, and n-acetyl glucosamine. These products may come in tablet, capsule, and powder forms. Glucosamine also is found in combination products, usually with chondroitin. Minerals and vitamins may also be included in these combinations, such as manganese.
Glucosamine hydrochloride has been reported to be better absorbed by the body, therefore being more available for use.
Glucosamine is also available as an injectable form that your physician can insert directly into the arthritic joint. N-acetyl glucosamine is also available as an enema.
How to Take It:
There is not enough scientific evidence to recommend the use of glucosamine in children.
For adults ages 18 years and older: Glucosamine sulfate or hydrochloride, 500 mg, 3 times daily, for 30 - 90 days. Once daily dosing as 1.5 gm (1,500 mg) may also be used.
Ongoing supplementation (roughly 1,000 mg per day) may be required to prevent the progression of osteoarthritis or to reduce pain and inflammation associated with the condition. Talk with your health care provider.
Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable health care provider.
The majority of studies indicate that glucosamine is safe, nontoxic, and causes only minor side effects such as stomach upset, heartburn, indigestion, gas, bloating, and diarrhea. If these symptoms occur, glucosamine should be taken with food. People with peptic ulcers should take glucosamine sulfate with food.
Glucosamine sulfate may contain high amounts of sodium or potassium, so individuals on a restricted diet or taking potassium-sparing diuretics should carefully check the label before taking glucosamine supplements.
People with diabetes should have their blood sugar checked regularly as glucosamine may cause insulin to work less effectively.
Some glucosamine supplements are derived from shellfish, so individuals with shellfish allergies should check with a health care professional before taking these supplements.
People who are allergic to sulfur are usually allergic to sulfa drugs or sulfite-containing food additives. Sulfur is an essential nutrient that is naturally present in the body of all individuals. "Sulfur-sensitive" people can safely use glucosamine sulfate. In these people, use of glucosamine hydrochloride would be recommended.
Glucosamine is not recommended during pregnancy or breast-feeding due to lack of scientific evidence in these people.
If you are currently being treated with any of the following medications, you should not use glucosamine or make any adjustments to your medications without first talking to your health care provider.
Nonsteroidal anti-inflammatory drugs (NSAIDs) -- Glucosamine may increase the anti-inflammatory activity of NSAIDs such as ibuprofen (Motrin or Advil). This interaction may result in the need for lower doses of these medications.
Blood sugar lowering medications or insulin -- Glucosamine may alter the need for blood sugar lowering medications and insulin. Check with your health care provider before taking glucosamine supplements if you have diabetes and require blood sugar lowering medicines or insulin.
Glucosamine sulfate; Glucosamine hydrochloride
Reviewed last on: 5/25/2007
Ernest B. Hawkins, MS, BSPharm, RPh, Health Education Resources; and Steven D. Ehrlich, N.M.D., private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.
Adams ME. Hype about glucosamine [editorial]. Lancet. 1999;354:353-354.
Chard J. Glucosamine for osteoarthritis: magic, hype, or confusion? It's probably safe-but there's no good evidence that it works [editorial]. BMJ. 2001;322:1439-1440.
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(8):795-808.
da Camara CC, Dowless GV. Glucosamine sulfate for osteoarthritis. Ann Pharmacother. 1998;32:580-587.
Das A, Hammond TA. Efficacy of a combination of FCHG49 glucosamine hydrochloride, TRH122 low molecular weight sodium chondroitin sulfate and manganese ascorbate in the management of knee osteoarthritis. Osteoarthritis Cartilage. 2000;8(5):343-350.
Deal CL, Moskowitz RW. Nutraceuticals as therapeutic agents in osteoarthritis. The role of glucosamine, chondroitin sulfate, and collagen hydrolysate. Rheum Dis Clin North Am. 1999;25:379-395.
Delafuente JC. Glucosamine in the treatment of osteoarthritis. Rheum Dis Clin North Am. 2000;26(1):1-11.
Gaby AR. Natural treatments for osteoarthritis. Altern Med Rev. 1999;4(5):330-341.
Gottlieb MS. Conservative management of spinal osteoarthritis with glucosamine sulfate and chiropractic treatment. J Manipulative Physiol Ther. 1997;20(6):400-414.
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;56(2):555-67.
Kelly GS. The role of glucosamine sulfate and chondroitin sulfates in the treatment of degenerative joint disease. Alt Med Rev. 1998;3(1):27-39.
Leeb BF, Schweitzer H, Montaq K, Smolen JS. A metaanalysis of chondroitin sulfate in the treatment of osteoarthritis. J Rheumatol. 2000;27:205-211.
Leffler CT, Philippe AF, Leffer SG, Mosure JC, Kim PD. Glucosamine, chondroitin, and manganese ascorbate for degenerative joint disease of the knee or low back: a randomized, double-blind, placebo-controlled pilot study. Mil Med. 1999;164:85-91.
McAlindon T. Glucosamine for osteoarthritis: dawn of a new era? Lancet. 2001;357(9252):247-248.
McAlindon TE, LaValley MP, Gulin JP, Felson DT. Glucosamine and chondroitin for treatment of osteoarthritis: a systematic quality assessment and meta-analysis.JAMA. 2000;283(11):1469-75.
McCarty MF. Enhanced synovial production of hyaluronic acid may explain rapid clinical response to high-dose glucosamine osteoarthritis. Med Hypothes. 1998;50:507-510.
Muniyappa R, Karne RJ, Hall G, Crandon SK, Bronstein JA, Ver MR, Hortin GL, Quon MJ. 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;55(11):3142-50.
Reginster JY, Deroisy R, Rovati LC, et al. Long-term effects of glucosamine sulphate on osteoarthritis progression: a randomised, placebo-controlled clinical trial. Lancet. 2001;357:251-256.
Rindone JP. Randomized, controlled trial of glucosamine for treating osteoarthritis of the knee. West J Med. 2000;172(2):91-94.
Salvatore S, Heuschkel R, Tomlin S, et al. A pilot study of N-acetyl glucosamine, a nutritional substrate for glycosaminoglycan synthesis, in pediatric chronic inflammatory bowel disease. Aliment Pharmacol Ther. 2000;14:1567-1579.
Shankar RR, Zhu JS, Baron AD. Glucosamine infusion in rats mimics the beta-cell dysfunction of non-insulin-dependent diabetes mellitus. Metabolism. 1998;47:573-577.
Thie NM, Prasad NG, Major PW. Evaluation of glucosamine sulfate compared to ibuprofen for the treatment of temperomandibular joint osteoarthritis: a randomized double blind controlled 3 month clinical trial. J Rheumatol. 2001;28:1347-1355.
Towheed TE, Anastassiades TP. Glucosamine and chondroitin for treating symptoms of osteoarthritis. JAMA. 2000;283(11):1483-1484.
Zupanets IA, Drogovoz SM, Bezdetko NV, Rechkiman IE, Semenov AN. The influence of glucosamine on the antiexudative effect of nonsteroidal anti-inflammatory agents [in Russian]. Farmakol Toksikol. 1991;54(2)61-63.
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