I have a couple of boys w/bad manners who, even after neutering, still sprayed on occasion. My vet gave me a drug for them called Clomicalm. It's usually prescribed for dogs w/behavior problems but it can be safely administered to cats as long as you don't over medicate them. They get 5 mg. before bed and virtually no more spraying. Believe me, I was ready to send one of my boys, Specs, to the moon! This saved him and my house and most importantly, I enjoy him so much more because I'm not mad at him all the time. Talk to your vet about Clomicalm if the spraying continues.