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Why is my 3-month-old puppy suddenly aggressive and biting family?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed | Male | unneutered

My dog 3 months old suddenly shows to much of aggression to my family and my other dogs and starts from today yesterday he is normal but today he shows aggression and trying to bite kindly help me out what's going on

3 Answers

Most Helpful Answer

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Answered By David Darvishian

Veterinarian

Published on December 13th, 2017

Hi and thanks for using Petco Pet Education Center, formerly Petcoach! Sorry to hear about Bruno. When a puppy shows aggression, I immediately advise neutering him to remove the male hormone-driven behaviors. I would advise taking him to your veterinarian for their opinion also. He may have some medical reason for his sudden onset of aggression. Your vet can gather a history, perform an exam and then offer a diagnostic/treatment plan based on their findings. Possible tests include fecal/blood/urine tests and x-rays to look for underlying medical problems that could cause aggression. If a behavioral problem is suspected, then neutering, behavior modification, and drug therapy can be tried. I wish you good luck with Bruno

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    Answered By Dr. Melanie, BVSc MS

    Veterinarian

    Published on June 18th, 2019

    This is some pretty serious aggression. First I would have Rudy neutered. Some aggressive behaviors can be hormonally related. Then speak to his vet about a referral to a professional behavioral expert. I never recommend owners work with aggressive dogs on their own due to the safety risks. The expert will let you know if his behavior can be corrected or if he needs to be put down. Best of luck.

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    Answered By Susan England-Foster

    Veterinarian

    Published on September 6th, 2018

    I am sorry you all are going through this with such a young dog. I am not sure what is available to you in India but in the united states I would recommend taking Prince to a vet to make sure he does not have any underlying health issues that might be coming out as aggression. Than I would recommend getting him in advanced aggression training. This would involve working with a dog trainer who specializes in aggression. The fear is with such a young dog if left unaddressed it could get worse. I would try and start working with him in other areas and try to keep him from sitting close to certain people that trigger his aggression. Hope this helps

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