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Flea Allergy Dermatitis


Have you noticed your dog scratching itself more than usual lately? Or perhaps obsessively licking or chewing at its fur in an effort to reach and satisfy a particularly persistent itch? If so, then it might be more than just a simple everyday irritant – it could be a sign of a much more serious skin condition called Flea Allergy Dermatitis, an extremely unpleasant dermatological disease with the potential for causing long-term damage.

So, what exactly is Flea Allergy Dermatitis and how can you protect your pet from it? Read on to find out.

What is Flea Allergy Dermatitis?

Flea Allergy Dermatitis (FAD), also known as flea bite hypersensitivity, is one of the most common skin diseases that affect dogs. Essentially, it’s an inflammatory response to flea saliva.

Fleas are one of the most widespread external parasites found on pets. These small, wingless bloodsucking insects feed off the blood of their hosts. When fleas feed, they inject a small amount of saliva into the dog’s skin. The saliva contains proteins (antigens) and histamine-like compounds that can trigger the dog’s immune system to overreact and cause an allergic reaction, resulting in extreme itching, fur loss and inflamed skin.

Flea Allergy Dermatitis can develop in any dog at any age, and it’s important to note that dogs with this hypersensitivity don’t necessarily have to be infested with fleas to have this reaction — often a single flea bite is enough to cause intense itching. As a result, dogs can damage their skin due to their constant scratching, biting, or licking in an effort to get relief, and this damage can lead to serious secondary infections.

What If Don’t See Fleas on My Dog?

Just because you may not see the fleas, it doesn’t mean they aren’t there.

Most of us assume that fleas are a seasonal issue, but it’s not actually true. Although we typically associate spring and nicer weather with fleas, any season is really flea season.

And so, it only makes sense that your pet can end up with fleas any time of year. Fleas lay their eggs on your pet, which can fall onto the floor or other surfaces as your dog moves around. At the pupae stage, adult fleas can remain in their cocoons for weeks or even months until a host is close enough for them to jump on.

So, while you may not see the fleas right away, you will see the evidence of the allergic reaction.

When dogs feel a flea bite them, they’ll scratch themselves and will sometimes chew and gnaw at their hind end near their tail, and/or jump up from a resting position. If you see your dog scratching severely enough that it leads to hair loss on the middle of its back all the way down to the base of its tail, then you need to consider that your dog may have Flea Allergy Dermatitis.

If left untreated, the hair loss can spread all over the body, including up to the head and neck.

In addition, when a dog scratches, licks, and chews, it breaks the skin which can cause open sores and scabs. The licking and chewing can also cause continuous moistened, reddened areas (hot spots) on your pet’s body that can lead to yeast and bacterial infections.

Signs & Symptoms

The most common sign of Flea Allergy Dermatitis in dogs is intense itchiness, but other signs to watch out for include:  

  • Appearing restless and uncomfortable
  • Spending a lot of time grooming; repeatedly chewing, biting, licking, and scratching themselves or rubbing their skin against objects
  • Fur may be stained brown from licking – this is especially obvious in white pets
  • Missing patches of fur or hair typically along the lower back and base of the tail, the thighs and belly
  • Skin rashes, reddened or darkened skin, thickened skin, abrasions or wounds from scratching
  • Hot spots or infected sores, usually located on the dog’s legs, hind end and tail

Flea Allergy Dermatitis can be a very uncomfortable condition for your dog, but the good news is that it’s preventable.

An Ounce of Prevention Goes a Long Way

Preventing, reducing, and eliminating flea infestations is crucial to prevent recurring Flea Allergy Dermatitis.

Treat Your Dog

Examining your pet regularly, coupled with using a monthly flea and tick preventative, is key to avoiding and controlling a flea infestation.

A monthly topical treatment that kills fleas on contact, such as K9 Praventa 360, is the most efficient way to eliminate them. Unlike oral medications, which work only once your dog has been bitten, K9 Praventa 360 not only repels and kills adult fleas on contact – meaning no biting required – but it affects each flea life stage, continuing to work by preventing flea eggs and larvae from developing. K9 Praventa 360 is an easy way to ensure your dog is protected year-round so you can enjoy any season flea- and tick -free.

Treat the Indoors

It isn’t enough to simply treat your dog for fleas; keeping your home free of these pests is also important. Fleas can quickly spread throughout the home. Just treating your pet without treating their environment only solves 50% of the flea problem. Indoor treatment measures include vacuuming (carpets, cushioned furniture, cracks and crevices on floors, and baseboards) and washing your pet’s bedding in hot soapy water.

Treat the Outdoors

It’s not just the interior of your home that needs attention, you need to treat the outside of your home as well. Oftentimes, your dog can pick up fleas right in its own back yard — usually from wild animals, such as squirrels, raccoons, or skunks, dropping flea eggs in the yard as they pass through it. Outdoor treatment measures include using a premise spray to kill flea populations that may be hiding in the yard or around the foundation, mowing your lawn regularly, and clearing away yard litter such as branches and leaves.

To learn more about how to get rid of fleas in your home, on your pet, or in your yard, click here.