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My cat is suddenly aggressive and moody. Is it a medical issue?

Updated on September 23rd, 2025

Pet's info: Cat | Bengal | Female | spayed | 13 years old | 0 lbs

My cat is always moody and aggressive and she never used to be!!!!?????

1 Answer

Most Helpful Answer

Answered By Jennifer Summerfield, DVM CPDT-KA

Veterinarian, Certified Dog Trainer

Published on May 25th, 2017

Since it sounds like this is a recent behavior change for Zora, I would be very suspicious that she may have an underlying medical problem causing her aggressive behavior. There are a number of common problems in older cats that can cause behavior changes like this, including hyperthyroidism, chronic kidney disease, or even pain from arthritis. I would recommend taking Zora to the vet for an exam when you are able to - he/she can do blood work if needed to check for these issues. If a problem is found, it's likely that it can be treated with medication to make her more comfortable and hopefully improve her mood as well :)

1Pet Parents found this answer helpful

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