Fear Aggression in Dogs – Causes & Signs to Help You Understand Buster’s Behavior

Fear Aggression in Dogs

Fear aggression in dogs can often be misinterpreted and may lead to undesirable consequences. Many people equate dog aggression as “bad behavior” which certainly deserves punishment whether physical, emotional, or mental.

This is also why a lot of dogs turn out to be more aggressive than they were before the punishment and pose serious threats to other people and pets. Although curbing your dog’s behavior is definitely important when they become aggressive, punishing them is not the proper method of dealing with it.

More often than not, the punishment will serve as an added stressor to the dog, causing them to become more aggressive.

Looking at how a wrong approach to correcting dog aggression can result in worse situations, it becomes necessary for a pet owner to fully understand what fear aggression is and how to deal with it.

A pet can easily become traumatized with a wrong approach which can affect not only the quality of life that they will have in the future but that of the owner as well. Just like in other types of problems, it is important to know what the problem is, what causes it, and how to deal with it before any real solution can be applied.

What Is Fear Aggression?

What Is Fear Aggression

Fear aggression is defined as aggression that is produced because of fear. For some people, this can be quite confusing since fear often will push a dog to flee and not to fight. So what causes a dog to become aggressive when in fact, what they want is to run away? In order to understand this, one should also take the animal’s physiological make-up.

When a dog experiences fear, their body’s hypothalamus is also triggered which is connected to their fight-or-flight mechanism: the sympathetic nervous system. Hence, a dog can react either by running away or by fighting the perceived threat when they are overcome with fear.

It is also important to note that when a dog is experiencing fear, its cerebral cortex is also shut down. Their sympathetic nervous system activates instinctual behavior and so your pet only acts based on how they immediately feel towards a particular situation without thinking about it.

This means that when they are afraid, they don’t think so attempts to get them to follow voice commands and orders may not be effective. The best way to modify their behavioral response to fear then would be to modify how they feel towards the object or person that they are fearful of.

What Causes It?

Dogs can become fearful of almost anything for a variety of reasons. It can range from a simple act of being taken by surprise to a traumatic experience that is somehow related to that object. Dogs of different ages and health conditions have a particular threshold in which they can cope with fear.

If that fear threshold is surpassed, then the dog will lash out and act aggressively especially when they feel that they cannot flee from the stimuli. It becomes their way of protecting themselves from the perceived threat by telling them to go away.


There are specific breeds of dogs that are more predisposed to being fearful than other breeds. Aside from that, these traits can also be passed on if the mother was in a state of fear and anxiety when the puppies were still being nursed by the mother.

Puppies can easily adapt to their parent’s character and disposition and this can be carried on as they grow up.


A dog that is not well-exposed to a particular stimulus will often be fearful of it. Hence, you will often see dogs that are aggressive towards strangers and unfamiliar pets. Since they do not know if the other party is a friend or foe, their best assumption is that they are threats.

This is especially so because the brain is more attuned to negative emotions which helps them to protect and preserve their safety. Unfamiliarity is often brought about by a lack of social and environmental exposure during their puppyhood days.

Traumatic experiences

Dogs that have undergone a traumatic experience and which have not been properly treated will continue to react with aggression whenever a similar stimulus is presented in order to protect themselves.

The fear of having to undergo the same pain is enough reason to try to get away from it or if they cannot, to make it go away.

Health conditions

There are also certain health or medical conditions which can make a dog fearful of physical pain and thus act aggressive. For example, a dog with arthritis can be scared that a child could accidentally step on their legs and thus protect themselves by snarling whenever children come near them.

Hormonal imbalances can also affect the emotional state of a dog which can make them snap at even the slightest touch or irritation.


There are cases when a dog can become fearful for no reason at all and it can all be traced to a defect in their overall cognitive ability.

Sometimes, a dog’s recognition of their own surroundings and even owners can be greatly affected due to the physical deterioration of the brain and hence, treat as strangers or aggressors.

What Are the Signs of Fear Aggression?

Fear aggression can be difficult to determine especially if the dog has successfully covered their fear by acting more aggressively.

But in its initial stages, aggression which is triggered by fear will show the usual signs of fear in the animal accompanied by a slight show of aggressive behavior. In most cases, the dog will act in the following way:

  • Stand still and body is rigid
  • Raised hackles
  • Ears are pinned back
  • Growl in a low tone without facing the stimuli directly
  • Show some teeth
  • Snarl
  • Nip or bite than run away afterward
  • Urinating or defecating while showing aggressiveness

This can change though when the dog has become somewhat of an expert in the field of trying to scare away the perceived threat. When a dog sees that growling or barking will successfully drive the perceived threat away, it will then try to use it more to its advantage.

Fearful dogs

Hence, a dog will act more aggressively and forcefully even when what they are actually feeling inside is fear for their safety and well-being. When this happens, people will equate that fearfulness with uncontrollable aggression and try to suppress that behavior by physical punishments which in turn add to the stress that the dog is already experiencing.

How Do You Deal With It?

Fear is closely associated with the hypothalamus which is the brain’s emotional center. It also activates the sympathetic nervous system which involuntarily controls the body’s reaction toward a threat such as increased heart rate, an increased supply of energy to the muscles, and the suppression of cortical thinking.

Dealing with aggression caused by fear should therefore center on the dog’s emotional responses to the threatening stimuli. So how do you teach your dog to control their fears?



Since unfamiliarity is one of the major causes of fear, it, therefore, follows that desensitizing them to what they fear is a good solution to fear aggression. This is done by gradually exposing your dog to the stimuli and by providing positive associations with them.

Since food is one of the greatest motivators of dogs, giving your dog bits of food or snacks while slowly introducing the stimuli to them will greatly help in changing their perception of the said threat.

Interestingly, digestion activates the parasympathetic nervous system which is associated with being in a relaxed state. Although this can take some time, especially if the fear is deeply ingrained, it should be done by a professional or by a dedicated pet owner.


One good way of providing relief from fear and anxiety in dogs is through good exercise. Physical activities release hormones that will help your dog feel good. It will also help get rid of excess energy which can fuel your dog’s anxiety.

A good walk in the park or around the block for about 15 to 30 minutes each day will give your dog a good emotional boost. Find out how much exercise your dog needs by reading our article, it’s a must-read.

Social exposure

If your dog is easily scared by strangers or strange dogs, then the best way to deal with their fear is to socialize them. This has to be done in a gradual way in order to prevent any adverse reaction.

You can try introducing a friend’s dog first going on to dogs that they may meet in the park in order for them to understand that strange dogs are not always a threat to their safety hence, there is no need to act aggressively. We’ve written a piece on puppy socialization to guide you in this area.

Treating any underlying medical condition

If the dog is suffering from hormonal imbalance, senility, or any condition which causes physical pain then having these conditions treated first will be of great importance. A dog that is generally feeling well will tend to have a better emotional disposition and will less likely snap when they are touched or approached.

This also includes providing your dog with the proper diet and hydration. For very aggressive dogs, a lower dietary protein content than the average is usually recommended.

Treating fear with medication

In cases of extreme fear or anxiety, your vet can recommend prescription drugs that can help calm the dog down. This is often done during visits to the vet or grooming clinics in order to lessen the risks of biting since they will be handled by other people.

Some of the more commonly prescribed medications are buspirone, propranolol, and fluoxetine. Remember that improper administration of these drugs can lead to lethal consequences so never give them to your dog without your vet’s prescription.

How Do You Prevent It?

Fear aggression can be best treated by preventing it from occurring in the first place. This means training Fido on how to socialize with other people and other dogs early in their life, taking care of their needs for health and safety, and making sure that they are not continually exposed to any type of situation which will make them surpass their fear threshold.

How Do You Prevent It

Here are some tips and information on ways to stop aggression in your dogs that we’ve written in an article, check it out.

Although it cannot be assured that your dog will never fear anything in the future, teaching and preparing your dog on how to handle such instances will be of great value.

Training your dog how to socialize

Socialization is a good way of teaching your dog how to interact with other people and pets that they meet either randomly or through visiting friends and relatives. By getting them exposed to other pets and persons, they will slowly gain familiarity and confidence on how to interact with strangers which will make them less fearful.

One other important aspect of socialization as well as your own attitude toward such events. If your dog senses that you are getting tense, they will imitate that emotion as well. If you are confident, then your dog will feel confident as well. Dogs which are socialized early on are less likely to be fearful of new people or pets. For more tips on how to socialize your pooch, see our earlier article on the topic.

Taking care of their health and safety needs.

An unhealthy dog will not be as sociable as a healthy one. If your pet’s diet lacks in the essential nutrients for their body and brain to function, they will be more irritable and fearful especially when the malnutrition affects their hormonal balance. Providing a good shelter for them is also important in helping them feel safe from any threat or harm to their well-being.

Build them a dog house or a room of their own where they can hide when they feel threatened. Don’t tie them up in an area where they can be taunted by children or passersby as this can increase fear, frustration, and anxiety which will lead to aggression.

Preventing too much exposure to fearful situations

As said earlier, your dog will have his own level of fear threshold so the situations that can provoke fear in him can vary from another dog. If you notice that your dog is fearful of a particular situation, don’t try to push him beyond his limits by repeatedly forcing him to face it. Stress hormones are released during such encounters which are not eliminated by the body easily and can stay in the body for as long as one day.

If you constantly expose your dog to such a situation, they will have a constant supply of stress hormones which will put them in a continuous state of anxiety. It will wear them out physically and will also cause their aggression to become more permanent and ingrained in their personality as the negative emotions become attached to the said event or stimuli. It can also lead to trauma which is definitely what you want your dog to be exposed to.

Another important thing to remember when dealing with fear aggression is that punishment is never a suitable solution for Fido’s behavior. Punishment indicates that he has done something wrong and fear can never be considered to be a wrong behavior.

When your dog acts aggressively out of fear, the best that you can do is to allay that fear and to personally take the responsibility of keeping the dog and other people safe. This can be done either by comforting your pooch or by protecting him from the perceived threat.

Touching or embracing the dog will help ease their anxiety and will also help them feel safe. If the other dog is being aggressive, then the best solution would be to leave the area.

Punishing the dog either by inflicting physical pain such as through prong or electric collars is a wrong and inhumane way to treat a pet. Putting them in isolation or tying them up will only worsen the situation since it does not allow them to really get to know the threat for what they are.

Inflicting physical pain, especially excessively painful ones, can suppress the aggressive behavior for now but it will never change your dog’s perception of the stimuli as a threat. On the contrary, it will reinforce the negative emotion associated with it through the pain that they experience whenever they come into contact with the threat.

Not all types of dog aggression are brought about by a bad character or personality; there are instances when it can also be caused by fear. A dog’s natural tendency to protect and preserve their own safety is a must for their survival and when they fear that this is being taken away from them, they can resort to aggression.

Take the time to train and desensitize your dog properly to objects and situations that they fear and make sure that you provide their basic needs for safety. Be careful in the methods that you choose to solve this aggression as the wrong approach can not only lead your dog to become more aggressive but it can damage them for life as well.