Bring in a urine sample asap.
My dog hit the sleds, same symptoms as your dog. The urine sample was what determined the problem. IMHO vets don't ask for this test enough.
It is relatively inexpensive, and tells a lot about what's going on. Pet owner's need to bring in urine more often for testing and insist on it being tested. Shouldn't be that way but sadly it is.
I always am the one to bring one in and insist on it. IMHO, urinalysis tells more than blood work AND you can send it in to culture to KNOW what antibiotic will work.
Also the antibiotic's complicate the whole not eating. Many state right on the insert will affect appetite. It's a double edged sword, and brings the dog down even more, to where you can lose the dog from them not eating due to the antibiotics more often than the cause of the illness.
My vet was insisting on tri-meth-sulpha it just about was killing my dog. I brought a urine sample in and had it sent out for culture and it came back showing it was sensitive to of all antibiotics.....ammoxi...,the antibiotic with the least side affects. :S
