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My senior dog is aggressive & destructive. Could it be dementia?

Updated on September 23rd, 2025

Pet's info: Dog | Lhasa Apso | Male | neutered | 11 years and 7 months old | 25 lbs

Hello, chewy has really been bad for the past 6-8 months and the vet thinks it’s due to dementia. He Potties everywhere, he gets into trash, chews and tears stuff up again, runs away, doesnt listen. A month ago he ripped a fence board off the fence for no reason.For the past couple of days he has attacked my kitten for no reason when they used to get along fine. He used to be well behaved and sweet. I’m afraid he’ll hurt my cat. He bit him hard but hesnot hurt. What can I do and is it dementia?

1 Answer

Most Helpful Answer

Answered By Dr. Heidi DVM, CVA, CCRT, CVTP, CVSMT, CVCH

Veterinarian, Certified Veterinary Acupuncturist, Certified Canine Rehabilitation Practitioner

Published on April 6th, 2018

I'm sorry that Chewy is showing such changes. The signs you are describing are possibly dementia, but are not the most common signs that we will see with dementia which we typically call Canine Cognitive Dysfunction (CCD). I am attaching a a handout about CCD below that discuss possible supplement and medication options for treatment.
https://www.veterinarypartner.com/Content.plx?P=A&S=0&C=0&A=2549
Since Chewy's symptoms are not typical of CCD and seem to be getting worse, I would have your veterinarian examine him again to see if there are any abnormalities on examination and consider consulting with a neurologist or behaviorist to assess the significant changes in behavior that you are noticing with Chewy.
You can find a neurologist near you here who can assess for any abnormalities on neurological examination.
http://find.vetspecialists.com/
A veterinary behaviorist is a veterinarian who has additional years of training in behavior. They can also prescribe medications if needed. Hopefully you can find one near you here.
http://www.dacvb.org/about/member-directory/
Good luck! I hope that was helpful and you can figure out how to help Chewy. Thanks for using PetCoach.

1Pet Parents found this answer helpful

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