Pharmacology: Glucosamine sulfate may stimulate the synthesis of proteoglycans and collagen by cartilage cells as well as perhaps inhibit enzymatic degeneration of collagen. Glucosamine does not produce direct analgesia.
Pharmacokinetics: About 90% of glucosamine administered orally as a glucosamine salt gets absorbed from the small intestine and from there it is transported via the portal circulation to the liver, with only 10% appearing in the feces. It appears that a significant fraction of the ingested glucosamine is catabolized by first-pass metabolism in the liver. The absorbed glucosamine, 25% will be excreted in the urine, 65% excreted as exhaled carbon dioxide, with the remaining 10% retained in tissues.