Why Does My Dog Keep Biting Herself?

I managed to find the answer to the question of why does my dog keep biting herself by boiling it down to internal and external reasons.

Once I ruled out parasites and skin issues, I started tackling the psychological problems.

For a while now, I’ve been catching my dog viciously chewing on her leg, as if she wanted to bite it off.

At first, I thought nothing of it and assumed that the problem would just go away on its own.

But after a few weeks of her gnawing, I began to worry because I couldn’t find the answer to the question of why does my dog keep biting herself.


Why Does My Dog Keep Biting Herself?

After extensive research, I found that a dog bites itself for either internal or external reasons.


External Reasons

External factors are usually related to skin issues, making them much easier to spot. They resemble dermatitis or a skin rash most of the time.

The rash is usually coupled with skin inflammation, swelling, and even hair loss in more severe cases.



Fleas are to dogs are what lice are to humans. In essence, they’re small critters that feast on the dog’s skin and can transmit a wide variety of diseases.

Since fleas are sometimes impossible to see with the naked eye, we need to devise a strategy to get rid of them.

The best way to deal with fleas is external deworming. The process involves applying an anti-flea solution with a pipette or using an antiparasitic collar.

However, I wouldn’t recommend this treatment for puppies, as they have extremely sensitive skin.

What’s more, keep in mind that a dog might be allergic to fleas, a condition known as flea allergy dermatitis (FAD).

If that’s the case, the dog will bite itself until it draws blood, have scabs all over its body, and be in immense pain.

Dog owners who suspect their dog has FAD should take it to the vet as soon as possible. A professional will prescribe a unique treatment plan and help the dog recover.



Similar to fleas, ticks are pesky little parasites that feed on animal blood. Since they connect directly to the pooch’s bloodstream, they can easily transmit diseases.

To remove a tick, we have to use special tweezers, grab the tick, and gently pull it upward. After that, we should disinfect the wound with povidone-iodine or chlorhexidine.

However, if we don’t know how to properly remove them or if our dog is infested with them, it’s best to go to a vet.

They’ll make sure that the parasite is gone and prevent future infestations.



Mites are another type of parasite that can wreak havoc on a dog’s skin and cause scabies.

Scabies is a contagious skin infestation that’ll make a dog bite and scratch itself. If it continues biting, the dog will experience hair loss and get scabs.

In more severe cases, usually with puppies or sick dogs, mites can even lead to death.

If a dog has mites, the first thing we need to do is take it to a vet, who will prescribe antibiotics and insecticides.



If a dog’s been exposed to mold for a while, it can get a fungal disease that will affect its skin, respiratory system, and brain.

Treating a mold infection is extremely difficult because it can easily come back.

So again, the best course of action is going to a vet, who will prescribe a unique treatment plan.



Another possible answer to the question of why does my dog keep biting herself is if it has picked up a bacterial infection.

If it’s already bitten itself raw and the wound stays exposed, it can develop an infection that’ll manifest as tiny red bumps on its skin.



Telltale signs that a dog has a yeast infection include itchy ears, hair loss, and skin lesions.

Most often, it’s just a symptom of a much bigger underlying issue, like a hormonal disbalance or an allergy.


External Parasites

In addition to ticks, mites, and fleas, a dog can also contract Cutaneous Leishmania, which it can later transfer to its owner.

A dog can contract it from a mosquito bite and the parasite will make its skin itchy.

Getting rid of this parasite is a challenge in itself and requires a lot of time, care, and patience.

That’s why it’s essential that we take our dog to a vet if we suspect it has leishmaniasis.


Atopic Dermatitis

Atopic dermatitis is a dog’s hypersensitivity to some common environmental factors.

For example, if a dog is allergic to pollen, dust mites, or mold spores, it will get an aggressive rash on its skin.

Atopic dermatitis is a genetic disorder that a dog is most likely to develop in the first three years of its life.

Some dog breeds, like Golden Retrievers, bulldogs, and terriers are more susceptible to allergies.

There are a couple of methods that can help dogs fight allergies, including medication and immunotherapy.



If a dog gets a small cut, it will usually want to bite it. What’s more, a dog that has a splinter embedded in its paw will chew on it to try and get it out.

However, as I already mentioned, an injury or a cut can quickly snowball into a much bigger problem and an open wound could easily lead to an infection.

That’s why, if we see any sort of lesion or nick on a dog’s body, we should clean it and apply an appropriate ointment to it.



Seborrhea is a pretty common skin condition, for both dogs and humans. It usually manifests as a red, itchy rash and can cause white scales on the skin.

In most cases, seborrhea looks like dandruff and is easily treated with a good bath and a medicated shampoo.

Some dog breeds, like terriers and basset hounds, are more susceptible to having seborrhea than others.

But it can also be caused by a hormonal disbalance, allergies, and food sensitivity.


Internal Reasons

While trying to answer the question of why does my dog keep biting herself, I discovered some internal reasons could be to blame.

These include some of the things I’ve briefly touched on like allergies, hormonal disorders, and stress.



Dogs can develop skin or food allergies, or be overly sensitive to different environmental allergens.

The most common symptoms of allergies include:

  • Swelling in the face and body
  • Itchiness
  • Redness
  • Hives
  • Vomiting
  • Diarrhea


If the allergies go untreated, a dog will most likely develop atopic dermatitis, scabs, and an infection.

In less severe cases, we can treat allergies with a change in diet and keeping our dogs away from environmental allergens.


Hormonal Disorder

If a dog has problems with its ovaries, testicles, adrenal or thyroid glands, it’ll most likely have a hormonal disorder.

The easiest way to spot a hormonal disbalance is if a dog has a rash on its skin and is biting itself in random places on its body.


Stress or Anxiety

Sometimes, none of these factors will answer the question of why does my dog keep biting herself.

If that’s the case, we have to examine our dog’s behavior and figure out if it’s feeling anxious or stressed out.

Another reason why a dog might start biting itself if it’s feeling bored, lonely, or restless.


Running Tests

The best way to determine why a dog is biting itself is by running a series of tests.

The most common types of tests include:

  • Cytology
  • Hair study
  • Skin scrapes
  • Allergy tests
  • Hormonal tests
  • IgE levels
  • Bacteria and fungi cultures
  • Blood tests


Of course, a vet will recommend one or more of these tests, depending on what they think the problem is.

Afterward, they’ll prescribe a treatment plan that usually involves some type of medication and certain lifestyle changes.


How to Stop a Dog Biting Herself

Now that we answered the question why does my dog keep biting herself, it’s time to talk about possible solutions.

But it’s important to remember that, if a dog has a skin condition, a simple pill or cream won’t be enough to make it go away.

With that said, once a dog has been diagnosed, we should first start by cleaning and sanitizing all the places where it sleeps, eats, and drinks, and giving it regular baths.

Most vets recommend giving a bath once a week and thoroughly drying the dog afterward.

We can also put an antibacterial collar or apply a vet-recommend solution after the bath.

On the other hand, if a dog has a food allergy, for example, we can buy hypoallergenic food. It is full of vitamins and has the nutritional value necessary to help our dog fight allergies.


Final Thoughts

These are the most common answers to the question of why does my dog keeps biting herself and how I can stop it.

But it’s important to remember that every dog is unique and might need specific treatment.

If the biting problem persists even after a dietary change, it’s best to consult with a vet and get to the bottom of it together.

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