Chondroitin was first extracted and purified in the 1960s. It is currently manufactured from natural sources (shark/beef cartilage or bovine trachea) or by synthetic means. The consensus of expert and industry opinions support the use of Chondroitin and its common partner agent, glucosamine, for improving symptoms and arresting (or possibly reversing) the degenerative process of osteoarthritis. Chondroitin is an ingredient found commonly in dietary supplements used as an alternative medicine to treat osteoarthritis. It is commonly sold together with Glucosamine.
Multiple controlled clinical trials since the 1980s have examined the use of oral Chondroitin in patients with osteoarthritis of the knee and other locations (spine, hips, finger joints). Most of these studies have reported significant benefits in terms of symptoms (such as pain), function (such as mobility), and reduced medication requirements (such as anti-inflammatories). Possible actions include promotion and maintenance of the structure and function of cartilage (referred to as chondroprotection), pain relief of osteoarthritic joints and anti-inflammatory activity.
Chondroitin sulfate is part of a large protein molecule (proteoglycan) that gives cartilage elasticity. It is another natural substance found in the body. It prevents other body enzymes from degrading the building blocks of joint cartilage. People who use these nutritional supplements hope that they will relieve the pain of osteoarthritis, and perhaps even repair or restore the joint cartilage. Recent evidence seems to support the first claim. Both Glucosamine and Chondroitin sulfate have been used in Europe for several years, with few reported side effects. Both supplements also have some anti-inflammatory effects that may account for the pain relief.
American Academy of Orthopaedic Surgeons. http://orthoinfo.aaos.org/fact/thr_report.cfm?Thread_ID=219&topcategory
PDR Health. http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/cho_0071.shtml