Behavioral problems

Why is My Dog Suddenly Aggressive Towards Me?

Josie F. Turner
By Josie F. Turner, Journalist specialized in Animal Welfare. July 22, 2018
Why is My Dog Suddenly Aggressive Towards Me?

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According to the ASPCA (American Society for the Prevention of Cruelty to Animals), up to 6.5 million animals are abandoned every year in the USA alone. One of the main reasons for abandonment is the aggressiveness these animals can develop either towards people, animals or other dogs.

Many people with dogs as pets may have experienced a seemingly unwarranted attack, even if it did not result in a dramatic situation. Have you ever held a dog by the collar to restrain them and they have snapped at you? Was your dog playing quietly in the park and then launched at another dog for not reason? If so, this AnimalWised article tries to answer why is my dog suddenly aggressive towards me? In doing so, we can try to stop it from happening again in the future.

You may also be interested in: Why Is My Dog Suddenly Aggressive Towards Me?
  1. Aggression in dogs
  2. Genetic basis of aggressiveness in dogs
  3. Redirected aggression in dogs
  4. Treating aggression in dogs

Aggression in dogs

Aggression can be exhibited through a wide variety of behaviors and for several reasons. We can observe two main types of aggression; offensive and defensive aggression. The risk factors of canine aggression include those which hurt the dog, the unpredictability of an attack, the stimuli to which the dog reacts, the triggers and circumstances which provoke the animal.

In general, offensive aggressions are those we need to correct the most. This is because some defensive aggressions are warranted if the dog is likely to be hurt. The expression of offensive aggression is controlled by the part of the brain which regulates emotions, memory, hunger and sexual instincts. Such aggression is influenced by the perception of the dog's environment via smell, hearing, sight, etc. It is also greatly influenced by the socialization of the dog, particularly in their younger years as well as the experiences they have throughout their life.

Defensive aggression is believed to be controlled by a different part of the brain. They also control the escape instinct, fear defense and biting. To know more, we have this article on understanding dog aggression.

Why is My Dog Suddenly Aggressive Towards Me? - Aggression in dogs

Genetic basis of aggressiveness in dogs

Many studies show that there is a genetic basis for aggressiveness in dogs and that each breed has the potentiality to be aggressive[1]. This means the gene is not only present in those considered ‘potentially dangerous’ dogs.

A recent study of Golden Retrievers showed that in 80% of cases, the aggressiveness is hereditary. Another study in Cocker Spaniels has shown a genetic influence on aggression according to the color of their coat. In English Springer Spaniels aggression is associated with genes passed down by the male during breeding.

Currently, there is no reliable test to measure aggression. The best information comes from people who live with dogs and have witnessed aggressive situations in real life. However, even with genetic influence on aggression in dogs, their environment plays an even greater role. Adequate socialization of the dog is crucial to avoid aggression, especially from early stages of the dog's life.

Redirected aggression in dogs

Redirected aggression is when a dog in an aggressive state redirects their aggression towards one source to another. A dog which is barking at someone behind a door, can redirect their aggression toward an owner who tries to open said door. Redirected aggression problems are more likely to occur when there is human intervention in a dog's conflict. For example, a human intervening in two dogs fighting may experience aggression directed towards themselves.

However, every time a dog enters this state, it doesn't mean redirection will occur. This is, in party, due to the hierarchical structures of a dog's family. Sometimes a dog will display aggressive to one member they deem themselves to be higher in the pecking order, while they won't do it to another.

Defensive aggression can also be redirected. For example, a dog that is frightened by the presence of strangers or terrified by loud noises might attack family members closest to them. This redirection of aggression is simply venting the frustration caused by these situations.

Why is My Dog Suddenly Aggressive Towards Me? - Redirected aggression in dogs

Treating aggression in dogs

When faced with aggressive behaviors in a dog, it is imperative that you see a dog training specialist. This is so they can apply the safest and most effective method for each individual dog. It is also necessary to help show the human members of the family how they can best deal with these problems. While it is advised for you to help train your dog basic obedience techniques, reducing aggression is not as easy as getting a dog to give you their paw. If you don't train them effectively, it can have terrible consequences. Alto, it is advised you should take them to the vet and ensure there is no underlying pathology which might have a bearing on their sudden aggression.

Each case of canine aggression is unique and and the success of the treatment depends on diagnosis as well as the capacity and motivation of an owner. Modifying behavior is a useful tool for animals which provoke aggression responses. These modifiers can include counter-conditioning, positive reinforcement, habituation and desensitization.

It is also important to know the difference between an aggressive dog and one which is playing. Just because a dog growls while they are playing doesn't mean they are trying to attack you.

If you have experienced issues with your dog making displays of aggression, please share them in the comments below. Also include the useful courses of action taken to reduce this aggression.

If you want to read similar articles to Why is My Dog Suddenly Aggressive Towards Me?, we recommend you visit our Behavioral problems category.

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We adopted a 5 year old female beagle named Chloe 5 months ago. She was raised for hunting, had little obedience training, and had never been properly socialized - which we only learned recently. She's always been more emotionally bonded to me it seems, though for a long while she displayed love for us quite equally.

My partner got a shock collar to help train her, mainly on walks as she is very impulsive and disobedient - we only ever used it once as we felt terrible with her reaction to the lowest shock setting. Since then, she's been afraid of him. It started with her growling at him when he walked by her sleeping. Then it turned to lunging and prowling. One night, she picked a fight with him, smelling his face closely then attacking him relentlessly with her teeth.

Since then, we've been trying to reset - crate training her and continuing with obedience training using positive reinforcement. For the most part, she has been a lot better with him. But sometimes, out of nowhere, she will go back to her old snarling and prowling. When this happens, she will sit when he commands her to, and will give her paw, but her tail will still be tucked between her legs.

We don't know what to do. Any advice? It makes the home rather tense!
I have a 3 mo old pitbull (55% pit) mix who has become extremely aggressive toward me and other dogs. I can no longer socialize her. I've been discussing her behavior with the rescue group and we've been trying different methods to stop this, but nothing seems to be working.
My dog is half lab and maybe half terrier. He is an outside dog and would growl or snap at strangers sometimes. He just got neutered two days ago and he has been more aggressive towards people that he knows well and has never growled at before. He is 2 years old.
Matthew Nesbitt (AnimalWised editor)
Hi Caroline,

We cannot confirm why your dog has become more aggressive, but we can say it is likely a temporary effect of the neutering. They simply may be scared and upset by the procedure, so it is best if you provide reassurance and affection. Do not scold them as it will only reinforce negative behavior. Their hormones will also need time to adjust, so hopefully they should not longer be aggressive after some time. If they are, or there is another reason behind the aggression, take them to a veterinarian.
Margrite Tebboth
My 8 month old dog has shown some sign of aggression if I took his toys away before being neutered. He was neutered 3 days ago and his aggression has markedly increased and he is very much more disobedient
Matthew Nesbitt (AnimalWised editor)
Hi Margrite,

We have just answered a very similar question, so please excuse us repeating the answer, but we think it should be helpful:

We cannot confirm why your dog has become more aggressive, but we can say it is likely a temporary effect of the neutering. They simply may be scared and upset by the procedure, so it is best if you provide reassurance and affection. Do not scold them as it will only reinforce negative behavior. Their hormones will also need time to adjust, so hopefully they should not longer be aggressive after some time. If they are, or there is another reason behind the aggression, take them to a veterinarian.
Same here I got my dog nwutered because he snapped at my grandddaughter, Its been a week and now hes snapping at me,, wtf
I have a 6 month old morkie. I got him fixed 3 weeks ago. Every since he was fixed he now shows signs of aggression. Before being fixed he was the sweetest pup. Example now if he is sitting beside you and you touch a blanket or anything near him he will jump at you snarling and try to bite you. He doesn't do this all the time. Please if there is any advice you can give me on how to stop this behavior please tell me. All of this bad behavior has been since I got him fixed Aug 26th. I love this little guy and want him to be happy.
Administrador AnimalWised
Hi Dana,

We cover this issue in the below article:

In most cases, the aggression should subside, but you may want to speak to your vet in case there is a specific problem which can be treated.
My 12 year old maltipoo occasionally wakes up attacking us mostly my husband what can we do?
We have had our 1st dog for 8 years. He is a begal terrier mix. He loves me and my kids but seems to dislike my husband. My husband also recently got a pitbull which is very agressive towards the 1st dog. The pit is 2 years old. But he seems to like our 3rd dog who just turn 1. Not sure what to do with pit or the older dog, We did not have any problems with the older dog until getting the pit. My husband was not always kind to the 1st dog when he was a pup but after I warned him I would not acccept him mistreating him he stop, at least as far as I know.
Administrador AnimalWised
Hi Regina,

If anyone mistreats an animal, it will result in trauma, behavioral problems and, likely, aggression. If the Pit Bull has been poorly socialized, abused and/or aggression is encouraged, it can be particularly dangerous. Our advice is to stop mistreating any animal in you or your husband's care. If abuse continues, it will be detrimental for everyone involved. It contravenes the animal's rights and is an inhumane practice.
Nancy Simmons
My son transferred ownership of his boxer/English bulldog to me and my husband. We have had him for about 2 months. My husband fed him the other night and as he walked away he turned to look at the dog. All of a sudden the dog started growling, lunged at my husband, and bit the crap out of him. My husband and I wonder if it could be because my son left him. Any ideas why this is happening.
I rescued a pitbull a year ago who had been severely beaten. He was in a foster home before me and since day 1 he has been completely loveable and calm in every situation. He's always been great with every person he's met since he's been with us, all he ever wants is love. Him and my German Shepard are inseparable. They do stay in a 12*12 kennel but they are both let out multiple times a day to run and play or just to get plenty of attention from us. And neither of them have ever had any issues with it, when we go back inside we tell them to go lay down and they go straight to their kennel so we can shut and latch the door with no problems. Until last night, when I went to put latch the door my pitbull jumped up in the door and started growling, barking, and trying to push the door back open on me. Then tonight he did the same thing but much more aggressively, I couldn't even shut the door so I just let him back out and tried petting him to calm him down and he was jumping up tryin to bite my arm ( I know he was tryin to bite because he never jumps up, not even when we are playing with him) so I calmly walked inside and got my finance so he could go put him up and he came very close to actually biting my fiance, my fiance had to use his foot to shove him in the kennel to shut the door. It was either that or potentially be attacked by him.
I just don't understand he has never acted this way about anything
Why has my dog suddenly became food aggressive. Towards my 6 and 7 year old. Alsk seems to not even want the 7 year old near him. Will lift lil if he comes to use and has now actually but both boy a day alrt
Administrador AnimalWised
Hi Danielle,

We are not sure. We have given some possible suggestions in the article, but we cannot diagnose anything in the comments to articles. A vet or canine ethologist visit is the best course of action to determine why their behavior has changed.
We have 2 boys (5 &10) and 3 dogs (4- maltese/havanese mix; 1.5-labradoodle & 9 weeks-golden doodle). Approx 6 months ago, the oldest dog started baring his teeth and doing a low growl when told to go lie down (go to his kennel). It has progressed quickly, to where not only would he do that, but if we walk behind him (herding him) to his kennel, or if I (alpha in home) pick him up, he actually tries to bite. He has gone for my face several time and my 10 year old twice (I am the inly one who picks him up). There are no other changes. Took him to the vet and was told (basically) to see a dog behavior specialist or give him away. Thoughts? Recommendations?
Administrador AnimalWised
Hi Chris,

This article might be able to provide some additional help:

Unfortunately, it sounds like the problem here is pretty severe. If you don't have the ability to train and educate problematic dogs (not many people do), then you will need to find someone who is able to. This requires a professional.
I live with my son and grandson. Their dog,, Spike, whom I’ve been around since he was adopted about 5 yrs ago. I was a very frequent visitor at the time. We actually started living together 3 yrs ago. Also, as a side note, I have two older Yorkies, but the three dogs get along fine. The problem is this - approximately 5 weeks ago Spike lunged at me, growling and showing his teeth. My grandson was a bale to pull him back and restrain him. After that incident Spike was acting like his old self with me. (I am the one who is home all of the time.) Then, about aa week later, he lunged at me pushing me to the floor. And again, my grandson was able to restrain him so I could leave the room. And again, he was acting like his same old self the next day. Just aa few days later, I was taking my Yorkies outside when Spike suddenly jumped and lunged at me, this time. He bit me on the forearm. Since that time he has remained in his kennel during the day. He displays no aggression towards me when he is kenneled. My son thinks that Spike”s actions are because “he is afraid of you (meaning me) and that I must have done something to him to cause this sudden change in behavior. I have thought about this and cannot think of anything that I have done differently with him. At this point, I am afraid of him ,and do not feel comfortable in the house with him when is out of the kennel. Just a FYI, Spike was born in the desert, near a friends home. They think that he was approximately 7 weeks old when he was brought homie. No one has been able to identify aa dominate breed in him.. He has shown aggression with strangers consistently but my son is uusuuallly able to settle him down before he is able to do any lunging, etc. I am to the point that I don’t know what to do and my son is not willing to discuss te situation to any extent except for random cryptic comments like the one above.
Administrador AnimalWised
Hi Denny,

If a dog is showing aggression in this way, then it cannot be tolerated. While you have been able to defend yourself up to this point, you may not be so lucky at a time when your grandson isn't present. Also, if Spike lunges at you, it is possible they may do the same to a more vulnerable person such as a child.

Puppies need to be with their mother for a minimum of 8 weeks, although 12 is much better. This is the time when they are learning socialization and this dog's behavior (more than breed) is likely to be due to poor socialization. Fixing this problem is not easy and may require the help of a canine ethologist or specialized dog educator.

The reason why he lunges at some time and not others can be difficult to determine. What is important is that they learn they cannot do it with anyone. Your grandson ignoring the situation is unacceptable. If Spike was to attack anybody in the future, not doing something about signs of aggression can be seen in some places as criminal negligence.

We are not saying we know why Spike is behaving this way (although we cover the main possibilities in the article). Nor are we claiming we know if he can be rehabilitated. We are saying that aggression like this needs to be treated otherwise it can lead to tragic consequences to both people and the dog.

Good luck and let us know how you get on.
K. Miles.
Have pit bull Cross lab rescue. He 3 yrs old recently castrated. He has new sister who is Spanish mastine. They have acres of land to be free and they get along together but recently rex the male has become aggressive just through stoking toward myself and my husband.
Administrador AnimalWised

Has your male dog been sterilized? Hormonal changes could be linked to aggression and neutering is a very effective way of reducing them.
My 1 and 1/2 yr old GSD lunged at my face viscously when I used a different type voice,he has never done that before,how I dealt with it was a blow to his face and scorned him,I’ve yet to trust him again
My 1 yr old female pit isn't aggressive towards people. But when certain things are in her mouth(other than her food which I have hand fed her before.) She feels the need to protect it and will lung and attack. Also so far has only been me. Who's with her 24/7 so I am confused as to why she is biting me for...she also has two bones. One that I can and have multiple times taken from her. Or walked by it etc and she doesn't get in defense mode or attack. But the other bone. Bigger and has a beef flavor on it... she has bitten me twice and broke skin both times because of me walking by it or her thinking I am going to pick it up. Mind you she is not in front of the bone and or chewing it. She was away from the bone both times. I don't kno whst to do. And I feel bad to give her to animal control and them put her to sleep her. She is very loveable dog. After she has bitten she knows she has done wrong and comes up to you with sad look and ears back...
She believes she is in charge of you and the leader of the household. If not corrected she will in time bite another human. This is an important time to get this under control. If she was taken from her litter too soon (under 10-12 weeks), this could be a factor, also see a vet to be sure there is no underlying medical condition, and to check the diet. Give her boundaries, exercise and get training.
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Why is My Dog Suddenly Aggressive Towards Me?