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How to stop my old cat from being aggressive to my new male cat?

Updated On September 23rd, 2025

Pet's info: Cat | American Shorthair | Female | spayed | 11 years and 8 months old | 9 lbs

I adopted a male cat 1.6 year old a month ago. My female age 12 isn’t a happy camper. She’s never been a people person anyway. She hisses at him and blocks him from eating sometimes. He’s very laid back and let’s her have her way even though she’s declawed and he isn’t. I’ve tried the melatonin collar and she chewed it off. Won’t eat the calming chews either. Should I just let it ride out and hope for the best? Thank u for any help u can suggest.

1 Answer

Most Helpful Answer

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Answered By Jenny, DVM

Veterinarian

Published on January 29th, 2018

The make feliway sprays and diffusers you can plug and spray on things to help that she will not be able to get to. If he is smart enough to walk away and not fight then I think they will be fine to figure it out on their own.

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