Sudden Onset Aggression in Dogs

Sudden Onset Aggression in Dogs

If a dog suddenly becomes aggressive for no apparent reason then it needs to be examined closely and carefully. There could be any number of reasons for it's aggression.Here are a few reasons that could lead to Sudden Onset Aggression.


Is the dog getting the correct amount of food? Is the food suitable for the breed of dog? Is the dog actually eating it's food or nibbling at it and then walking away? There are certain ingredients in some dog foods that could cause your dog to develop aggressive tendencies.Has the dogs diet been changed recently? Is it being fed a diet that has an adverse effect on it's mind or brain?


Is the dog ill? Does it have a fever, stomach pains or maybe even a tumour? A vet visit might be called for to illiminate any potential illnesses. Infection in your dog causes it pain as it does in humans, check it's teeth. An acquired condition could also be cause for upset. Your dog may have been in contact with a dog that has a contagious desease and has shown no outward signs of this. Take your dog to the vets as soon as you can.


Have you moved recently? Is the dog in a smal enclosed space, when it used to have more room to move and sleep? Does the dog still get regular exercise? Do you still have the same amount of time to walk your dog and spend quality time with it?


Genetics can play a role in the development of aggression. Do you know your dogs background? It's breeding? Take some time to research your dogs background, his parents and grandparents, see if there is something there that can cause your dog to become aggressive. Inter breeding in some cases can lead to aggression in some dogs. This may take time to manifest itself which could be why your dog has shown no signs of aggression before. As a puppy there may have been no signs, even as he grew up the signs may not show, it only takes a small trigger to start the aggressive tendencies which if not diagnosed by a vet or psychologist may turn into full on aggression.

Social Ranking

Has your dog suddenly been lowered down the rankings in your home? Have you got a new partner? Have you had a new child in the home? has your dog been relegated to a kennel outside because you have a new person or animal installed in your home?Hormone imbalance in bitches has also been known to cause sudden onset aggression as does a pseudo pregnancy, this can be cured by hormone balancing and neutering after the pseudo pregnancy has passed. Get your vet to check the dog out.Hydrocephalus is a medical condition that can be manifested only as aggression, it is an accumulation of cerebrospinal fluid in the brain because it's normal outlet is blocked by desease or malformation. This can only be diagnosed by a vet and needs extensive treatment.

Need to be alone

Does your dog just want to be left alone? When he is in his bed does he get disturbed by noisy children wanting to play. If he constantly gets disturbed he may turn to aggression to warn off the intruder into his bed, this can manifest into aggression for no reason, if he thinks he is going to be disturbed it might be a case of attack is the best form of defence and uses this when he thinks his personal space is being invaded.

Mental Lapse

This can occur when there is a sudden onset of pain or serious illness. Your dog can forget you are the one that cares for it, feeds it and generally loves it. The pain is so sudden that it forgets all that and turns on you. This is upsetting for you but has no effect on the dog, he only knows that the pain he is feeling hurts and in his head it could be you that is causing it.


In general if you dog does suddenly become aggressive, for no apparent reason that you can think of, the best thing to do for yourself and your dog is to get him to a vet as soon as you possibly can, like any illness early diagnosis could give him a better chance if he is ill.Keep a diary of the dogs aggressiveness, times. places, what happened before it became aggressive, what you fed it, if you walked it and where you walked it, have your circumstances changed enough to affect the dog, anything that may help the vet in his diagnosis.No matter what you may think the reasons are for your dogs aggression get a vet to check the dog, if the vet can find no reason for it then it's up to you to find a reason for it.

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