Will Falconer, DVM Moderator
Hi Stephanie, I'm so sorry your brother lost one of his dogs to kidney failure. And I think it's doubtful the Apoquel gets the blame.
First, "acute" kidney failure means a sudden onset and by definition, a short lasting phenomenon. Animals are typically NOT euthanized for acute kidney failure. They are put on IV fluids and usually, the condition resolves.
If it doesn't resolve, it's then realized (after a week or two) that this is indeed not acute but rather "chronic" kidney failure. And for that to be the diagnosis, it had to have started long before. That's the nature of chronic disease: it's slow, smoldering illness that comes on gradually and gradually gets worse. So, if the ultimate diagnosis was (most likely) chronic renal failure, it was likely just below the detectable level for some time. Typical signs are increased thirst and frequent urination with often pale or clear urine and perhaps some intermittent vomiting.
So, not to say Apoquel "upset the apple cart" and brought this already sick dog into full blown obvious kidney failure, but it wouldn't have caused chronic kidney failure in so short a time (and that's what I'm guessing was the final diagnosis, as again, euthanasia is not the norm for acute kidney failure).