Glucosamine is usually made from seashells, or it can be made in the laboratory. Hydrochloride is a salt form of glucosamine. Glucosamine in the body is used to make a “cushion” that surrounds the joints. In osteoarthritis, this cushion becomes thinner and stiff. Taking glucosamine hydrochloride as a supplement supports joint health by helping to supply the materials needed to rebuild the cushion.