The antiprotozoals don't make any sense to me, and it's not something I've heard of in connection with arthritis - would you mind explaining? Haven't heard of vitamin C, either, but given that it's a necessity for healthy connective tissue, it makes some sense, though dogs generally make enough on their own.If it's arthritis, first try an anti-protozoal drug like Metronidazole, plus Glucosamine supplements to rebuild his joints. Even if your vet won't go for the anti-protozoal drugs, at least try the Glucosamine.
I have great news. They are keeping Harley!!!
There is a fund for him at penn.