Glucosamine and chondroitin
Glucosamine and chondroitin sulfate are partner compounds that naturally occur in the body and are key components of cartilage and connective tissue. These substances have a long history of use in veterinary medicine to treat arthritis-related inflammation and pain in horses and other animals. Chondroitin has been used in Europe for over 20 years as a treatment for osteoarthritis and glucosamine became popular as chemical supplement for the treatment of arthritis (particularly osteoarthritis) in the late 1990s, when its use was recommended in the best-selling book The Arthritis Cure by Jason Theodosakis, MD.1,2
As with all supplements, whether vitamins, minerals, herbal or chemical products, consult with your doctor before you start taking glucosamine or chondroitin. There may be health risks associated with use of these compounds, including interactions with medications that you are taking and negative effects associated with health conditions you may have. Your doctor is also in the best position to determine the proper and safe dosage for any supplement.
Understanding chondroitin and glucosamine and their benefits for joint health
Chondroitin sulfate supplements are manufactured from cartilage in pork, cattle, and sharks, or produced synthetically. Chondroitin is an important component of proteoglycan molecules found in cartilage and works by attracting water to cartilage, thereby improving its ability to absorb shocks and impacts associated with physical movements and activities. It also inhibits enzymes found in synovial fluid that cause the destruction of cartilage while stimulating the production of chemicals that improve the viscosity of synovial fluid.1
Glucosamine supplements are manufactured from shellfish (crabs, shrimp, lobster). Glucosamine plays a key role in the formation and maintenance of cartilage. It was first used for the treatment of osteoarthritis in the late 1960s. Given intravenously, as a direct injection into the joint space, or as an intramuscular injection, it has been found to improve joint mobility and decrease joint pain.2
What is the evidence for the benefit of glucosamine and chondroitin?
There is consensus among arthritis specialists that supplementation with chondroitin and glucosamine is useful in preventing and reversing the process of joint destruction in osteoarthritis.
There is strong evidence of the effectiveness of chondroitin in osteoarthritis (in the knee and other joints) from randomized, controlled trials, where it resulted alone and in combination with glucosamine in a reduction of symptoms, including swelling and joint pain, and improvement in function (walking ability). The supplements were as effective as the non-steroidal anti-inflammatory (NSAID) ibuprofen (Advil, Motrin) in reducing pain and inflammation, but without the typical side effects associated with these drugs.1 Use of glucosamine to improve symptoms of osteoarthritis (particularly in the knee) is also well supported by clinical evidence.2
When it comes to the benefits of glucosamine and chrondroitin in RA, the evidence is much less clear. Only a few small studies of glucosamine as a treatment for RA have been conducted. In one study, a glucosamine supplement was compared with the NSAID indomethacin. Both treatments resulted in significant improvements in relief of pain, with glucosamine associated with a slightly greater improvement in pain from pressure applied to joints. Neither treatment resulted in significant improvement in functioning or joint swelling. Another small study evaluated potential anti-rheumatic effects of glucosamine in RA. Although there were no significant improvements in the rate of ACR20 responses and levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were unchanged, glucosamine did appear to result in patient-reported improvements in symptoms.2
Although chondroitin sulfate has been shown to inhibit enzymes in synovial fluid that are linked to destruction of cartilage in rheumatic disease, there have been no clinical studies to date evaluating chondroitin in patients with RA.1
Supplement dosing and brands
Chondroitin. Dosing of oral chondroitin supplementation in studies conducted in osteoarthritis ranges from 200 to 400 mg 2-3 times daily (or once daily at 800 to 1,200 mg). Higher doses do not appear to improve efficacy. In treatment of osteoarthritis, it may take several weeks before full effect is achieved. Several brands of chondroitin are available, including Structum, Matrix, and Condrosul.1
Glucosamine. In clinical trials conducted in patients with osteoarthritis, oral glucosamine dosing (tablets or capsules) of 500 mg 3 times daily have been used. Several brands of glucosamine supplements are available including Arth-X Plus, Flexi-Factors, and Glucosamine Complex. Glucosamine preparations may vary in quality by manufacturer and batch.2
Several glucosamine chondroitin combination supplements are available, including CystoProtek, Optisol, and Viscoat.