Glucosamine sulfate is usually derived from shellfish; the overwhelming number of joint health supplements containing glucosamine - including Tissue Rejuvenator - use shellfish-derived glucosamine sulfate. However, since glucosamine is derived from the shells of these animals while the allergen is within the flesh of the animals, it may be safe (key word 'may') to use Tissue Rejuvenator even for those with a shellfish allergy. Still, we adamantly recommend that anyone with a shellfish allergy consult their physician before taking Tissue Rejuvenator or any glucosamine sulfate-containing supplements.
While some companies may still use shark cartilage as the source material for chondroitin sulfate, Hammer Nutrition uses only highly purified and sterilized, 100% BSE (Bovine spongiform encephalopathy)-free, bovine-derived chondroitin sulfate produced in the USA.