Friendly dog suddenly aggressive. Is it from an old head injury?

It would be unusual for this to occur secondary to a bump on the head, but it is possible to see personality changs with major head trauma. I would recommend having your vet examine him again to look for signs of neurologic problems. Your vet can also refer you to a behaviorist who could help determine whether or not this is simply behavioral and unrelated to the accident.

With any sudden new behavior such as aggression in normally well behaved pets, it is best to schedule a vet visit. Pain and underlying illness can sometimes lead to sudden aggression or other behavioral changes which can lead to one dog attacking another, or the dog in pain becoming overly defensive and causing fights as a way of protecting itself against the perceived pain. Having both pets checked out for any issues is a good idea. If they both check out healthy, speaking with a trainer that can observe the behavior in person (and/or taking video to show a trainer) may help figure out if there is a cause to the sudden change and what can be done to help.

You need to take him to a vet for an exam. Any abnormal behavior, especially towards the side of aggression, need to be taken seriously. It very well could be a brain tumor. I don't know. It could also be the beginning stages of seizure activity. It could be from pain somewhere in/on his body. He needs a vet exam to try to find out what is going on with him.

I'm sorry to hear that you're having this problem! It's unusual for behavior issues like this to develop out of nowhere this late in life, so yes - it's certainly possible that he may have had a stroke, or some other neurologic problem such as a brain tumor. Certain systemic illnesses like hypothryoidism, Cushing's disease, or pain from arthritis or other problems can also cause behavior changes and increased aggression in older dogs. I would recommend taking Rio to the vet for an exam to discuss this problem when you are able to. Your veterinarian may suggest blood work, x-rays, or other testing to help check for these problems. Many of them are very treatable once a diagnosis is made, so there's a good chance that your vet may be able to help.

Hi there. It's unusual to see aggression issues suddenly start in a dog this age without any history of aggression, so I would be suspicious that Danny may have a medical problem causing this. He may be painful or uncomfortable for some reason, or may have a hormonal problem such as hypothyroidism or Cushing's disease causing him to be more irritable. I would recommend taking him to the vet for an exam and possibly lab work to see if an underlying cause can be found.

I would take him to a vet for an exam. Often times in older dogs, they can have aggression due to pain. This is often due to arthritis. Dogs can have cognitive dysfunction that can alter their behavior or a brain tumor. Your vet can check for anything signs that can help differentiate to see what your best options are for medicines

Oh dear! That is a worry for sure! It's really important that you don't get hurt, because dog bites can be pretty serious. I would suggest making an appointment with your vet to talk about possibilities. They might be able to link you up with a behaviorist, or dog trainer that could help a lot. There also could be medications that might help. Or, like you said, there could be a medical problem that is upsetting him.

Hi there. Yes, this definitely sounds concerning. Sudden behavior changes are often due to an underlying medication problem - Wanda may be in pain or not feeling well, or may have ingested something toxic that is causing neurologic symptoms. I would recommend taking her to the vet for an exam right away. He/she can do blood work or other testing if needed to help diagnose the problem and get her started on appropriate treatment.

Any dog that all of a sudden acts aggressive it is usually due to some type of pain in the body. If he is not eating he may have an intestinal obstruction and that is painful. I suggest you get him to a vet for an exam.

I'm sorry to hear that you're having this problem! If this has been a fairly sudden behavior change for Elsa, the first thing I would suggest would be to have her examined by a vet to see if there may be a medial reason for the aggression - many illnesses including thyroid problems and neurologic issues can cause sudden mood swings and behavior changes like this, as well as anything that may be painful such as an injury of some kind, arthritis, etc. If your vet determines that Elsa is healthy, then I would strongly recommend making an appointment with a veterinary behaviorist as the next step. Aggression towards humans is a serious and complex behavior issue that needs to be handled by a professional who can work with your dog in person. The behaviorist will evaluate your dog and help you determine what is triggering the aggression, then put together a detailed training plan to work on the problem. You can search for a board-certified veterinary behaviorist in your area here: ww