Been using it for about 2 months now. My 15 year old cat with chronic kidney disease, just had a vet check up, and his creatinine went up from 2.9 to 3.2. So kidney disease is still progressing, but slowly. I had hoped it would stabilize or go down. Plan to keep using it, and we will check again in 6 months. At least he is not having any symptoms, like his brother did before he died of it last year.