Some reading from a vet site ........
There is an ongoing debate amongst health experts on the question, "Is creatine safe?" This debate is tied in with the use of steroids and other muscle and size enhancing drugs.
Creatine is different from these other drugs because of its origins; it is a natural amino acid that is built up in the body through normal processes. It is also built up in your dog's body. However, there is little reason to use creatine for your dog. While studies are still inconclusive as to whether or not creatine is safe for your pet, it is best to avoid using this supple