My cat is a growling, hissing maniac .. any advice welcomed!

Here is the letter I wrote to his vet, it is from his perspective (or my interpretation of his perspective):

Hello Human! My name is Opie and I am a 22 month old Orange Tabby. I have one feline brother named Murfee and he at one point was my buddy but not lately - our friendship is a little strained right now! My brother and I were adopted within 3 weeks apart when we were 9 weeks old (we are not from the same litter or same mommy - other than my human one).

Here is my problem; I have a aggression issue against one of my humans ( I love my human mommy but I have begun to even hiss and growl at her). The thing is I only do this sometimes, mostly after I have been yelled at or said NO to (this is not a universal 24/7 anger issue, just many moments in a day)! There are the couple (maybe 3-4) occasions that I have lashed out at my human and I don't understand why I do this because I really do love my human – he feeds me, pets me and makes sure I am comfortable. I have lashed out at my brother Murfee (a couple times and was put in my place by him) but my humans were not sure if I was being aggressive towards him or not, I told my humans I was playing with Murfee, but I do not think they believe me! 

I know my humans want to help me but they simply do not know how and we were thinking that you might be able to help all of us. It is important to note that my brother Murfee (he is 21 months old) does not do this and is a even keeled cat, me on the other hand I am a little stressed out and tightly wound and would like help to not lash out at my human! I tend to growl and hiss at him, but after I am punished and left alone for a couple of hours I tend to snap out of it. I do have moments where I am in his lap, but then he will go to the bathroom or get water and I will be all snarly barley at my human daddy when he returns to the couch (That is what my humans call me)!

Please help us! My humans can only handle so much and they are getting ready to consider rehoming me (which I know my humans don't really want they are just lost and dont know how to help me)!

Thanks for any advice you can give them!

Any questions I can answer to help you help me, my humans will be happy to answer!

Opie

wow. i hope you don't end up rehoming Opie....

here are some things to consider:

1) hissing, behavioral changes can often times be caused by an underlying medical issue. Please get kitty to the vet as soon as possible. My girl Jet used to hiss for no reason, any time i got close to her. took her to the vet and she had worms. definitely take kitty to the vet.

2) do invest in some cat calming treats for Opie. it has helped both of my cats in situations of aggressive cat on cat behavior

3) separating Opie from Murfee is good when they are fighting, however, you have to keep the separation to only a few minutes, as animals don't understand why something is happening, and cats will not know what to associate the separation with if its something that lasts hours, and not just minutes. 

4) try to get both Opie and Murfee engaged in play. Watch our for the body language of an irritated cat (tails twitching, ears back) and distract the kitty with a toy. It works for my Charlie. He's older than Jet, and is very keen on proving his dominance.

5) do let your cats....duke it out (for lack of better words). They need to communicate to each other whats okay and whats not okay. If you feel that they are always going at each other, you might want to do a re-introduction.

6) keep in mind, murfee can most likely sense that opie might be sick, this could lead to them fighting a lot, as healthy animals don't want sick animals near them. also, it kind of ties in with the theory of your cat hissing and attacking you because he's sick. could be correlated.

first and fore most please take opie to the vet.

I hope this helps...please update the progress! i hope all works out well.