dog constantly biting and scratching

Key takeaway

If you find your dog struggling with constant itching and scratching, it may be a sign of an infection or hormonal imbalance and allergen or some other health condition. This itching and scratching is known as pruritus and can be addressed through veterinary care and medication.

We never like to see our furry friends struggling to relieve an itch they just can't scratch, but it's not always easy to tell what is causing their irritation.

Itching in dogs is known as pruritus, and this can often be a symptom of a more serious health issue. Your pup’s scratching and itching may be a result of allergies, infections, parasites, dermatitis, anxiety or another skin or sensory-related condition.
In this post we'll talk about some of the skin conditions that cause itching and scratching in dogs, as well as how to prevent and treat these bouts of irritation.

Why Your Dog is Constantly Biting and Scratching 

There are many reasons your dog may be itchy to the point of constant biting and scratching. Some of the common causes of pruritus include:


Excessive scratching may be a sign that your dog is suffering from an infection, whether that be caused by bacteria, virus, or fungus (such as a yeast infection). Consult your veterinarian if you notice that your pet is itching or scratching themselves more than normal. If your pet does end up having an infection, it's important to address the condition as soon as possible before it worsens

Parasites are common causes of itching and scratching for your pet


Parasites are one of the more common causes of itching and scratching for your pet. While you may be able to 

spot fleas and ticks with ease, certain parasites might not be visible to the naked eye until an infestation grows large enough. Your veterinarian can examine your dog for the presence of parasites, and prescribe the appropriate treatment options to alleviate their symptoms sooner. 
Here are some of the most common parasites that cause itching in dogs:

  • Fleas
  • Mites
  • Ticks
  • Lice


Allergies can manifest in many different ways in our pets, but if your dog seems to be biting and scratching excessively at their skin, it could be that they’re having an allergic reaction. Food allergies, environmental allergens, insect bites, and seasonal allergies can all lead to skin inflammation and itching.² 

Other common symptoms of an allergic reaction in dogs include:

  • Itchy/watery eyes
  • Cough
  • Hives
  • Facial swelling
  • Runny nose
  • Chest tightness/pain
  • Itchy skin

If your dog is biting and scratching due to allergies, removing the allergen in its immediate environment may help provide relief. In order to eliminate the allergen causing itching and scratching, you need to get rid of possible allergens one-by-one, which could involve phasing out new introductions to your pet's diet. Additionally, your veterinarian can prescribe medications that can help.

Contact Dermatitis

Dermatitis is a general term that describes any type of skin inflammation on your dog. Signs of dog dermatitis may include redness, swelling, skin bumps, and hair loss.  Long-term dog dermatitis can lead to infections and more serious skin conditions. Dermatitis may be the result of an allergic reaction. If you find your pet struggling to relieve an itch, contact your veterinarian and inspect your pet's skin to see if you find any abnormal irritation there.

Long-term dermatit

Hormonal Issues

The underlying reason for your pet’s skin condition may actually be caused by a hormonal imbalance, especially if you notice thickness or consistency changes on your pet’s skin. Diabetes in dogs and hypothyroidism can sometimes cause itchy skin, which is why catching signs early is vital. If you find lumps or bumps or other skin irritation is causing your pet to lick scratch or chew at their coat, you should contact your veterinarian.

 Dog Who is Constantly Biting and Scratching

How to Treat a Dog Who is Constantly Biting and Scratching

In order to help your vet properly diagnose your pet’s ailment, consider keeping a log of the symptoms your pet experiences. These notes will often serve as a helpful starting point as your vet reviews your pet's medical information and any acute areas of inflammation or irritation.

To accurately diagnose your dog, your veterinarian may perform a physical examination.They will also likely ask you about when symptoms started, as well as any changes in your dog's environment, such as food or  shampoo. This is why keeping a few notes about any changes in your dog's routine can help your specialist figure out what is causing the irritation.
Following a physical examination your vet may go on to perform a few other tests in order to figure out what is causing a flare-up of symptoms. Here are some other common ways your vet can diagnose your pets’ itching and scratching:

  • Skin swab
  • Ear swab and cytology
  • Blood chemistry panel
  • Skin allergy testing

Treatment Options for a Dog Who is Constantly Biting and Scratching

If you do see your pet being tormented by belts of itching and irritation, don't fret, because there are solutions. While some causes of pruritus have no cure, you can manage flare ups with the proper treatments::

  • Anti-itch medication
  • Allergy medication
  • Parasite medication
  • Removing allergens from the home

Other ways to help reduce flare-ups of irritation include ensuring a healthy diet as well as regular outdoor time and exercise. When you are outside, pay particular attention to the plants and environment your pet comes in contact with.You might find the culprit is somewhere along your walking path. 

My Dog is Constantly Biting and Scratching: Frequently Asked Questions

Why is my dog so itchy but has no fleas?

If you find your dog is itchy but don't see any signs of fleas, then the skin condition may be caused by another invisible allergen, such as pollen. Itchiness and skin irritation can also be caused by hormonal imbalances and infections which is why it's important to seek treatment early.

What can I give my dog for itching and biting?

It's important to seek professional help when trying to diagnose and treat pruritus in your dog.  Because the cause of your dog’s itching and scratching  can vary, having the support of a specialist who can properly diagnose the symptoms is important. One home remedy that may help ease symptoms is oatmeal which has commonly been used to soothe dry and itchy skin. However, you should only use home remedies with the guidance of your veterinarian, as attempting to treat your dog’s itching yourself can worsen their symptoms.

Why is my dog biting at himself?

Your dog might be biting or scratching at their skin because they are trying to ease the irritation caused by a skin disorder. Sometimes the cause of this order is easier to identify,  like the introduction of a new food, but other times, it’s not so straightforward. This is why a physical exam is usually the first step, and why you should always consult with your veterinarian before trying to treat your dog’s symptoms yourself.

What can I put on my dog to relieve itching?

Avoid using home remedies on your dog until consulting with your veterinarian. Certain home remedies can actually worsen your dog’s symptoms, so your best option is to get in contact with a professional as soon as you notice signs of itching. 

Final Notes

Because the cause of any itching or scratching may vary from an allergic reaction to an infection, it's important to seek veterinary care as soon as you notice your dog is struggling with symptoms. This way, thatYour veterinarian can pinpoint the cause of the pruritus and get your dog the right medication to help ease their skin inflammation.

Skin irritation and itchiness can be a real drain on your dog's well-being, but Dutch can help you find the right answers by connecting you with a licensed vet, so you can get treatment for your dog quickly.


  1. Moriello, Karen A. “Dermatitis and Dermatologic Problems in Dogs.” Merck Veterinary Manual, Merck Veterinary Manual, June 2018, 

  2. Moriello, Karen A. “Itching (Pruritus) in Dogs.” MSD Veterinary Manual, MSD Veterinary Manual, June 2018, 

  3. Diaz, Sandra. “Canine Atopic Dermatitis.” Merck Veterinary Manual, Merck Veterinary Manual, Aug. 2020, 

  4. Dryden, Michael W. “Fleas of Dogs.” Merck Veterinary Manual, Merck Veterinary Manual, June 2018,