there is one company that i know of within the united states that sells a pharmaceutical grade supplements for dogs AND cats.  The supplements are made in a full-licensed FDA facility AND are also made in the State of California which is ever more stringent in terms of regulation.  The supplements are made by a company called Integrated Pet Solutions, in Los Angeles.  I've checked around and they seem to be the only company making to human-grade standards.  Actually, their supplements are better than a lot of the stuff that is out there for humans.  Website is located at www.IntegratedPets.com, or www.seniorpetproducts.com.  Hope this info helps.