Sassy is on Azodyl for her kidneys. I went up to our vet to buy a bottle and make a payment on my outstanding vet bill. Got the meds, and my vet came out with another half used bottle that someone had donated. It was an amazing thing. And it helps me out alot money wise. So next time you don't finsh or don't need the leftovers, see if your vet will take them and give them to a person in need.