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Why is my senior dog aggressive, confused, dilated eyes, and peeing inside?

Updated on September 23rd, 2025

Pet's info: Dog | Labrador Retriever | Male | neutered | 9 years and 10 months old | 95 lbs

My dog is 10 years old and recently has become very aggressive. Also his eyes are dialated and glassy. He chases me in my car, on my lawn ,over and acts like he wants to bite. He is also tearing household trash up and began peeing and pooping in the house. He head never done these things. I’m afraid his mind is going. Is that possible?

1 Answer

Most Helpful Answer

Dr. Melanie, BVSc MS

Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on September 5th, 2020

Yes, that could be possible. Dogs can develop canine cognitive dysfunction, which is essentially dementia in dogs. This can cause behavior changes. Being sick can also lead Nelson to act aggressively because he feels so badly. I'd have him seen by a vet first thing in the morning for a health check. If he does have canine cognitive dysfunction, it can be managed with diet and medication. I hope this helps!
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