Chondroitin sulfate is a natural component of cartilage. It is extracted from shark or cow cartilage or manufactured synthetically. It is frequently combined with glucosamine.
(See also Overview of Dietary Supplements.)
People most often take chondroitin sulfate by mouth for osteoarthritis. For arthritis, it is frequently taken along with glucosamine. Scientific evidence shows little benefit when chondroitin sulfate is taken by itself, although quality of life may improve. In Europe, pharmaceutical grade chondroitin, available by prescription, may help osteoarthritis symptoms. In the United States, evidence suggests that combined with glucosamine, chondroitin may reduce joint pain and improve joint mobility.
The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
National Institutes of Health (NIH), National Center for Complementary and Integrative Health: General information on the use of chondroitin sulfate as a dietary supplement