I would not give him his insulin on an empty stomach. He needs to see a vet soon as he may be in kidney failure. t his age with his health issues this is not something to wait to see a vet for. If you cannot have him seen tonight he needs to go first thing when your vet opens in the morning. Try anything as far as food goes- baby food, canned cat food, tuna- if you have a syringe that you can put something in to squirt in the side of his mouth. Hopefully he will keep it down once you get some in.
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