I'm not one for medicating a cat unnecessarily but if one is aggressive to the point of drawing blood, I'd say a little amitryptilene is in order. One of my males, Specs, is aggressive and was attacking my other older male and was making life quite miserable for ol' Boo Bear. I have a deaf cat also and he played too rough w/her, to the point of making her hiss and that just isn't like li'l Creamsicle. She's one happy cat and just doesn't hiss or growl. And Specs would spray, too, which didn't exactly endear him to me. LOL But Jenluckenbach suggested amitryptilene and, for the most part, it works. Specs is sitting on my lap now as I'm typing this with his head tucked into the crook of my elbow. You might want to talk to your vet about it and determine the dosage. It sure helped me out and w/8 cats, I like to keep the peace!

Blessings,
M