Glucosamine is an amino sugar that is produced naturally in humans. It is also found in seashells, or it can be made in the laboratory. Glucosamine hydrochloride is one of several forms of glucosamine. It is important to read the labels of glucosamine products carefully since several different forms of glucosamine are sold as supplements. These products may contain glucosamine sulfate, glucosamine hydrochloride, or N-acetyl-glucosamine. These different chemicals have some similarities. But they may not have the same effects when taken as a dietary supplement. Most of the scientific research on glucosamine has been done using glucosamine sulfate. See the separate listing for glucosamine sulfate. The information on this page is about glucosamine hydrochloride.