Is My Dog Allergic To Fleas?

As if fleas could get any worse ... 🤢

Itchy dog

Your dog is scratching way more than normal, and you’re starting to notice some hotspots on his skin.

He’s behind on his flea medication — but you don’t see any fleas on him. So that can’t be it, right?

If this scenario sounds familiar, it’s actually very possible your poor pup has flea allergy dermatitis.

The Dodo reached out to Dr. Ursula Oberkirchner, a veterinary dermatologist and owner of Advanced Veterinary Dermatology in Florida, to find out what flea allergy dermatitis is and how it can affect your dog.

What is flea allergy dermatitis?

Flea allergy dermatitis is an allergy to flea bites — and it’s actually super common in dogs.

“Flea allergy dermatitis (FAD) is one of the most common allergies in our dogs and cats,” Dr. Oberkirchner told The Dodo. “If this animal gets bitten by just one or very few fleas, it will become severely itchy and the downward spiral is then allowed to begin.”

An allergic reaction to fleas is really uncomfortable for pets, and it’s far more annoying than a normal reaction to a flea bite (which is bad enough).

“Dogs and cats who suffer from FAD typically are severely itchy and often require veterinary care to help them become and stay comfortable,” Dr. Oberkirchner said.

Oftentimes, it only takes one flea to cause a reaction, which means you may notice a reaction but not see fleas or flea dirt on your dog. Even if your other pets are totally fine and you can’t spot a single flea in your house, it’s still very possible your dog has a flea allergy.

“It is important to know that FAD is not the same as a flea infestation. If someone has a flea infestation in their home, most animals (and humans) will itch somewhat, and one can often see fleas on the animal(s) or in their environment,” Dr. Oberkirchner said.

“This is in stark contrast to FAD,” she added. “In FAD, it is often a single animal that is affected and, typically, the owners have never seen fleas on their pet(s) or in their environment.”

Signs of flea allergy dermatitis

If your pup has flea allergy dermatitis, he might show the following signs:

  • Inflamed skin
  • Bald spots
  • Increased licking, scratching and chewing on the skin

“Most dogs with FAD itch along their back or base of their tail and, in turn, they often lose hair in those areas and develop secondary skin infections, which make matters significantly worse,” Dr. Oberkirchner said.

If you notice your dog showing these signs, you should take him to the vet immediately. They’ll be able to prescribe medications that can help him feel better fast.

Treatment of flea allergy dermatitis

Your veterinarian can help you determine the best way to treat your dog if he’s having an allergic reaction to fleas.

Some possible forms of treatment include the following:

  • Cytopoint: an anti-itch injection that lasts four to eight weeks
  • Apoquel: an immune-modulating pill that helps with both itch and inflammation
  • Cyclosporine (or Atopica): an immune-modulating pill that targets inflammation

There are some over-the-counter (OTC) medications you can use, like antihistamines, but these won’t be as effective as prescriptions — and you should ideally use them under the guidance of your veterinarian.

If you choose to give your dog an antihistamine, make sure it doesn’t contain decongestants or alcohol, which can be dangerous for him.

Try this dog-friendly antihistamine from Amazon for $3.60

Antihistamines don’t actually do much for a dog’s itchy skin, so it’s recommended that antihistamines are taken with an omega-3 fatty acid supplement.

Try these Zesty Paws Omega Bites from Amazon for $25.97

You can also try Zesty Paw's full line of allergy support products here.

How to prevent flea dermatitis symptoms

Although you can’t prevent your dog from developing flea allergy dermatitis, you can prevent his symptoms by keeping fleas away from him. And the best way to do this is by keeping your dog on a reliable monthly flea and tick medication.
This is important for every one of your pets, not just your dog with FAD.

“To help prevent symptoms of FAD from occurring in the first place, it is crucial to use excellent and continuous flea prevention for all animals in the household,” Dr. Oberkirchner said.

Try K9 Advantix for dogs on Amazon for $28.98

Try Frontline Plus for dogs on Amazon for $36.98

Try Simparica prescription medication for dogs on Chewy for $103.70

If you suspect your dog is allergic to fleas, don’t worry too much about it. After a visit to your vet and a product (or two!), your pup will be healthy in no time.

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