Posted 19th March 2010
Glucosamine may help to prevent cartilage degeneration and to treat arthritis, but patients with seafood allergies should avoid taking it, because it is manufactured by processing the crushed shells of crustaceans and therefore may lead to an allergic reaction in individuals who are allergic to seafood.
There have also been reports suggesting an interaction between warfarin and glucosamine (an increase INR has been noted in patients taking glucosamine supplements). The mechanism of any interaction is unclear, however, patients on warfarin are recommended not to take glucosamine.
Reference - Current Problems in Pharmacovigilance 2006;31: