Glucosamine and chondroitin are elements of cartilage found in the human body. Glucosamine, which is also known as chitosamine, is also found in the external covering of shellfish and can be synthesized. Chondroitin is both found in nature, for example in the cartilage of sharks or cattle, or made in a lab. Joined together as glucosamine chondroitin, they form a supplement that is sold to help joint flexibility and movement for people with conditions like osteoarthritis.
Glucosamine is available in several different forms. These include N-acetyl-glucosamine (NAG), glucosamine hydrochloride, and glucosamine sulfate. Chondroitin is also available in various forms, including chonsurid, chondroitin sulfate, and chondroitin sulfuric acid. The combination of the two products as glucosamine chondroitin may be sold in a variety of forms including capsule, liquid, powder, and tablet. Glucosamine chondroitin may also be combined with other ingredients.
Glucosamine chondroitin is regulated as a food rather than a drug and sold as an herbal supplement. There are no standards for its manufacture, which means that the oversight is not as complete as it would be if it were considered a drug. Consequently, various batches may not be similar in consistency, potency, purity, and quality. In fact, some shipments of glucosamine chondroitin have been found to be contaminated. This means that one should purchase the product only from a reputable manufacturer.
Certain conditions contraindicate the use of glucosamine chondroitin. A person considering taking the supplement should check with his or her healthcare provider if he or she is allergic to shellfish, has a bleeding disorder or blood clotting disorder, is overweight, or is on a low-salt diet. Glucosamine can increase glucose levels in the blood, so a person with diabetes should check with his or her healthcare provider because taking glucosamine chondroitin could modify the necessary insulin dosage. Additionally, a woman should check with her healthcare provider before taking glucosamine chondroitin if she is pregnant, planning to become pregnant, or breast feeding a baby. In addition, this supplement should not be taken in combination with chitosan.
A called the GAIT study (Glucosamine/chondroitin Arthritis Intervention Trial) reported in 2008, looked at glucosamine and chondroitin sulfate together. While it did not fare better than the placebo in slowing the effects of knee osteoarthritis, an erring prediction about the placebo group made the study difficult to interpret. A small group of study participants — those with moderate to severe pain — found relief that was significant from the combination of glucosamine and chondroitin.
