My elderly cat was diagnosed with CRF over two years ago. The vet at the time didn't have a very encouraging prognosis, but as a former vet student myself, I went home and did my homework. I found www.felinecrf.org and saw several recommendations for Azodyl. I have no doubt that Azodyl works and works wonders. VetDepot has the best prices and the cold packaging is second to none. They are actually the first site where the medicine arrived as cold as it should.