[anonymous]

Excerpt from:https://www.vetinfo.com/is-it-safe-to-use-human-glucosamine-for-dogs.html
Is It Safe to Use Human Glucosamine for Dogs?
Given the fact that the human glucosamine and the dog glucosamine have the same formulation, the human glucosamine can be safely used in canines.
However, it is highly important to have the right dosage for your pet and never go over the recommended dose. The dose for a larger dog breed may coincide with the dose recommended for a human patient, but smaller dogs need less glucosamine. An excess of glucosamine can lead to bone growth abnormalities and even internal damage. The administration of glucosamine supplements may also affect the liver and the kidneys of the pet in the long run. 
In any case, if you have the choice, it’s better to get glucosamine for veterinary use, as certain glucosamine for humans use have various salts that are included in the drug and these may irritate the dog. Be sure to talk it over with your vet first, as unique factors for each dog may need to be taken into account.
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