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My cat is suddenly territorial, hissing in a corner. What to do?

Updated On September 23rd, 2025

Pet's info: Cat | Domestic Shorthair | Male | neutered | 8 lbs

My cat setup a corner of my house as his territory and not allow me / my husband to enter suddenly. He will hiss and chase us after we enter it or touching the objects within the territory. What can we do?

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2 Answers

Most Helpful Answer

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Answered By Jessica Desrosiers

Veterinary Technician

Published on September 8th, 2017

Sudden behavioral changes can sometimes indicate pain or an underlying illness, so if this came on suddenly a vet visit is always a good first step to rule out any health problems. If your kitty is in good health, looking for something that may have triggered it such as a new object, new people, possession over toys etc may help you understand what caused it. Stress can make cats act uncomfortable or unpredictable, so removing the stressors or making it so your cat has a place to escape and relax may help him feel better. Pheromone diffusers/collars can also be useful in dealing with stress and aggression, and placing one on your cat or plugged into the area where he is being territorial may help him calm down.

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    Answered By Susan England-Foster

    Veterinarian

    Published on September 4th, 2017

    Most cats are aggressive due to stress in the environment. However I would recommend taking him to the vet to just make sure he is healthy. IF he is healthy you can try feliway a pheromone to help decrease stress. Also increase exercise, hide toys around house and increase levels with cat trees. All these things help the cat use energy and help decrease aggression. hope that helps!

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