Supplement is used for kidney disease and I have to say so far it has been working well. I have two senior kitties, one is 19 and we discovered she was stage 2 about 3 years ago, and Pronefra helped her keep it at stage two this entire time and even made her better. Second kitty is our newest addition who is 13 and came to us with stage 3 kidney disease earlier this year. She is taking it as well and we are so grateful that cascade veterinary is able to ship it to me in Calgary within 2 days which is so much faster than most places I was buying it in in Calgary. Highly recommended!