Seeing fleas creep through your pet’s fur is upsetting, but when those pesky parasites cause your four-legged friend to experience an allergic reaction, the situation becomes much worse. Flea bite allergy, or flea allergy dermatitis (FAD), is a leading cause of allergies in pets. Read our Neighborhood Veterinary Centers of Waller team’s guide to FAD, and learn how this condition can affect your pet. 

How does flea allergy dermatitis develop in pets?

FAD occurs when a pet’s immune system has an exaggerated response to flea bites. When a flea bites a pet, the parasite injects saliva into the dog’s or cat’s skin. If the pet has FAD, their immune system reacts to a protein in the flea saliva. Although these blood-sucking parasites are tiny, a few flea bites can trigger an intense allergic reaction in affected pets. 

Pets of any age can develop FAD, which is much more common in pets who already have an itchy condition, such as an environmental allergy to pollen or mold. Essentially, the immune system is already primed to mount an overactive response to an allergen, and flea saliva is a common culprit.

What are flea allergy dermatitis signs in pets?

Because your pet will be unable to hide their FAD signs, you are likely to spot your furry pal’s problem and seek treatment. If your pet has FAD, they will exhibit signs such as:

  • Intense itching — Pets with FAD are intensely itchy (i.e., pruritic) and will lick, chew, or scratch their skin until it is raw.
  • Skin inflammation — Red, irritated skin is pets’ hallmark FAD sign.
  • Hair loss — The classic FAD hair loss pattern is described as the flea triangle, a hair loss pattern that extends from the middle of the back to the tail base and down the hind legs.
  • Hotspots — Excessive licking and scratching can create acute moist dermatitis (i.e., hotspots), manifesting as raw, oozing sores. The fur is often matted over these spots.
  • Restlessness — Because FAD causes intense itching, pets who have the condition are often restless, irritable, uncomfortable, and unable to relax.

How is flea allergy dermatitis diagnosed in pets?

A pet’s FAD diagnosis is relatively straightforward, provided they have no other allergies. Our Neighborhood Veterinary Centers of Waller team can often make an accurate FAD diagnosis based on your pet’s signs and their rapid response to treatment. However, if a pet with FAD also has other conditions, such as environmental or food allergies, serum or intradermal allergy testing may be necessary for your veterinarian to make a definitive diagnosis.

How is flea allergy dermatitis treated in pets?

FAD treatment focuses on eliminating fleas from your pet and their environment, and alleviating their itching and inflammation. Therapies may include:

  • Flea prevention — Year-round high-quality flea prevention is the most effective way to treat and prevent FAD. Any lapse in prevention leaves your pet unprotected and susceptible to an allergy flare.
  • Corticosteroids — While not recommended for long-term use because of adverse side effects, steroids are highly effective at halting allergy-associated inflammation. 
  • Anti-itch medications — For pets who have multiple allergies, anti-itch medications, such as Apoquel and Cytopoint, are often administered to reduce the inflammation and irritation flea bites and environmental allergens cause. These medications are much safer than steroids when used long-term.
  • Antibiotics — Pets can cause secondary skin infections from excessive chewing and scratching. Our veterinary team will prescribe antibiotics if your pet has developed a bacterial skin infection.
  • Medicated shampoo — Medicated shampoos that include a steroid component can soothe your pet’s itchy skin and speed healing.
  • Environmental treatment — If you see adult fleas on your pet, keep in mind that they make up only 5% of the total flea population in your environment. The other 95% consist of eggs, larvae, and pupae, which linger in your home, mainly in your carpeting, furniture, and pet’s bedding. Eliminate the entire flea population by thoroughly vacuuming your home often, laundering your pet’s bedding in hot water, and using a pet-friendly flea spray that provides long-acting residual activity. 

A pet with a flea infestation, particularly one who suffers from FAD, typically also requires tapeworm treatment. When a pet bites and chews at their skin, they can ingest tapeworm egg-carrying fleas. Once inside your pet, the eggs hatch and mature, requiring treatment to prevent additional health issues.

FAD can cause your pet significant discomfort. Although the condition can be easily treated, flea prevention is simple, and prevents your pet from suffering extreme itchiness and additional potential health issues. If your furry pal suddenly becomes less furry on their hind end, and they are licking, chewing, and scratching excessively, schedule an appointment with our Neighborhood Veterinary Centers of Waller team.