Flea Allergy Dermatitis in Dogs

An itchy condition that will drive your dog crazy

Think: itchy! That is how your dog feels with flea allergy dermatitis. Flea allergy dermatitis is a very common allergy in dogs and is caused by flea bites; more specifically, flea spit (yes, spit). A flea’s saliva causes your dog to become very itchy and often puts them at risk for secondary skin infections. Often, the allergic reaction is mistaken for a rash.

The vile flea
It doesn’t take many fleas to cause your dog to go into a scratching and grooming frenzy. In fact, sometimes you won’t see ANY fleas at all because your pooch has removed them while grooming herself.

Any dog can become allergic to the bites of fleas, so it is important to learn how to care for your dog when he or she has fleas.


If your dog is plagued with flea allergies you may see the following:

  • Hair loss
  • Scratching of self, sometimes intensely 
  • Chewing, biting at the tail, hind end, and legs (most often, the hind legs)
  • Open, oozing sores
  • Skin damage due to scratching/licking

While flea allergy dermatitis is a very common allergy in dogs, other disorders can cause similar symptoms. Your veterinary staff may recommend tests to rule out other common problems. They will take a thorough history of your pet’s behavior and symptoms and perform a thorough physical exam. Your veterinarian will most likely use a “flea comb” to look for the signs of fleas, including the fleas themselves and flea “dirt,” which is actually flea waste. If fleas are present, they may recommend controlling the flea problem as a first step to determining why your pooch is so itchy. If fleas are not apparent, they may recommend tests to rule out other causes, such as food allergies, mange, mites, or ear infections. Additionally, they will recommend treatment for any secondary issues that have resulted from your dog’s intense scratching, such as wounds or open sores.

There are two important components to treating your dog for flea allergies. The first is to control the fleas and prevent your furry friend from future bites. Your veterinarian can recommend an aggressive and, more important, safe flea control for your dog and her environment.

Your veterinarian will also treat any secondary infections as a result of the flea allergy. Treatment often includes antibiotics and medications to help control the itch. Getting the itch under control is key!

The best way to prevent flea allergy dermatitis is to prevent your dog from getting fleas! Talk to your veterinarian about a safe and effective flea preventive for your pet.

If you have any questions or concerns, you should always visit or call your veterinarian – they are your best resource to ensure the health and well-being of your pets.

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