I guess if it were my dog
, and I was not convinced about the diagnosis of
Diabetes, as being the cause of
her problems, I would definitely have the vet check her for Cushings..this would explain the swollen belly, excessive drinking, and skin issues, and muscle weakness... I would also have the vet check for the possibility of Hypothyroid. From what I understand, Cushings and Hypothyroid, often go hand in hand.
I wish you the best with your dog.