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Updated on September 23rd, 2025
Pet's info: Cat | Mixed Breed | Male | 10 lbs
My other cats (4) are attacking only one particular cat. They have never been aggresive to him before until now. They are so mean to the point they try and attack me when I separate them. This has never happened before I am not sure what to do. I separated them last night and this morning let them out to see if the separation helped. They attacked again had to reseperate. Is there anything I can do to help, or any ideas as to why this is happening so suddenly with no changes to them or environme
2 Answers

Answered By Dr. Elizabeth
Veterinarian
Published on April 10th, 2019
Answered By Jessica Desrosiers
Veterinary Technician
Published on October 15th, 2018
A sudden behavioral change can sometimes indicate underlying illness or pain, so it would be best to bring both cats into your vet for an exam to rule out any health issues as a first step. If they check out healthy, making sure both cats have their own access to food, water, litter, bedding, etc may help decrease inter-cat aggression. Adding in a pheromone diffuser such as Comfort Zone can also help with stress and aggression between cats. If the behavior continues, speaking with your vet or a veterinary behaviorist to see if additional training options or a combination of training techniques and medication is beneficial may be a good idea.
You can find a list of veterinary behaviorists and more about them here: http://www.dacvb.org/about/member-directory/
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