Ah, quicker than I thought! I had just posted this and wanted to copy/paste instead of re-type...
Feline Redirected Aggression
This is a response the cat has to a sight, sound, smell or memory that triggers this behavior.
They are acting instinctively and really cannot help their response. It is like a person afraid of mice, or spiders. They will become frightened and react, EVERY time; screaming, jumping, flailing and/or running to get away. They cannot NOT be afraid of the mouse or spider, they just ARE and will react.
It is similar for kitties experiencing redirected aggression:
The cat sees, hears, smells something that activates its' instinct for survival (fight/flight
), but if he cannot reach the source of this trigger, he "redirects" it onto those around him; other pets and his people. The best way to handle a cat in the throes of a redirected aggression incident is to handle it as little as possible and/or try to get it into a small room to hang out and calm down by itself. The best way to prevent these incidents is to reduce and/or eliminate the triggers so it doesn't happen. You can use some products like a pheromone 'calming odor' in the form of a Feliway plug-in, it looks/works like an air-freshener but the odor/pheromone tells the cat "all-is-cool, be-mellow". You can also use other natural things, like Composure Liquid or Rescue Remedy to help keep him calm.
Maybe someone else will be able to give you better advice. I've only experienced Redirected Aggression once or twice, but neither episode was as bad as what you've described. I was attacked by a new cat when he smelled the outdoor tomcat on my hands. He yowled and leapt at me, I turned my face and upper body and he just scratched my shoulder badly. He did that because I smelled like the rival tomcat and his instincts took over.
Best of luck,
Redirected Aggression article from LBC: http://www.littlebigcat.com/index.php?a ... acasestudy