My cat has to go on a prescription diet because of kidney disease?

Just like with prescription drugs, prescription food can be obtained at places other than your vet. You get a prescription and then the online retailer will send it to you. Generally it's at less cost than the vet can offer it. As long as this is a reputable online retailer, it's the same food that your vet offers. And surely we all are looking for ways that save money without compromising the health of our cats!