You do not need or want to feed the presciption foods. They hold no value over commercially available canned foods and are very poor quality. For that type of money you can feed top of the line canned foods like wellness. If you cannot afford that then any canned under 10% carbs is best. Many diabetic owners feed low carb fancy feast. The key is no dry foods. This list gives the breakdown http://www.geocities.com/jmpeerson/canfood.html
Don't starve your cat though. If he won't eat canned make sure he eats and we can work on the transition over
Are you hometesting? it is the only way to know if it is safe to give insulin as well as giving the info needed to treat this disease safely and correctly. I can teach you how.
Your results will be more accurate then those gotten at the vet's office due to stress and other factors. It saves money in the long run but more importantly, saves lives.
I can teach you how
It is important to note that NONE of us here are veterinarians and can only relate our own personal experiences which may have no bearing at all on what you are dealing with personally with your cat.
TCS long-term members will share their experience and recommend you discuss these issues with your vet. For behavioural issues often our experienced members have a lot of knowledge and information which will not be a danger to your cat to try. But when it comes to medical issues, please work with your vet.
If you follow any medical type advice given by an individual member and anything happens to your cat, TCS will not be held responsible.