Flea Bite Allergies - June 2020

This month’s article continues the discussion on allergies. Flea bite allergy is a type that is seen often at our clinic. It is seen in dogs and cats of any age but most common in 3 to 5-year-old animals. The only good thing about flea bite allergy is that it is easy to treat! The bad thing about it is that fleas can be difficult to eradicate once they are in your home. Those are just two reasons why flea prevention is very important for your furry friends.

What does one see when an animal has a flea bite allergy? Itching is the usually the first thing, other signs are hair loss, redness of skin, and crusts or flakes depending on the severity of the case. The signs are usually acute in onset. In cats, excessive grooming may result, and hairballs may increase due to the over-grooming. The owners may see the fleas in the fur of the animal but it is less commonly reported with cats.

The animals that are allergic to the bites are reacting to the proteins in the saliva of the flea, leading to a hypersensitive reaction in the skin. There are several different immunological reasons for these reactions, but I will spare you of the academic details at this time. Dog or cats that have atopic dermatitis, which I detailed last month, are more prone to flea bite allergy due to their already sensitive skin. To reiterate another point: there is NO difference in the appearance of these two skin diseases, flea bite allergy must be ruled out first!

When seen at our animal hospital, the animal may have red skin, may or may not have hair loss, secondary skin infections, and black specks may be seen in the fur. The black specks are called flea dirt, but it is not dirt, it is the feces of the fleas! Gross! The pieces are dried up blood specks that were left by the flea after it was sucking the blood of the animal it is living on. Gross! This is not always seen at home due to the fur covering the cat or dog, and people at home don’t often inspect their own pets. The combination of the history of fleas, and skin disease makes flea bite allergy a relatively easy diagnosis. It can be easily treated, by eradicating the fleas, and medicating the secondary skin disease.

Flea prevention is the way to avoid this problem. There are many products out there that are designed to kill and prevent flea infestations in dogs and cats. Not all of these products are the same in effectiveness, or duration of efficacy. At St. Francis, Bravecto is our top choice for flea and tick prevention due to its efficacy, its 3-month duration when given, and safety of the drug in that product. However, we know that sometimes other products need to be used for flea prevention. Trifexis is a flea/heartworm/intestinal parasite preventative that is very effective, it is given monthly. Sentinel is a flea/heartworm/intestinal medication given monthly, while generally effective to prevent flea infestations, would not be recommended for a dog with flea bite allergy because the fleas do not die right away when they bite the skin. Also, we use a topical solution of Bravecto to place on cats, and for dogs that don’t want to eat the chewable version.

To summarize, flea prevention is key!! It keeps fleas out of your home, prevents your pet from getting flea bite allergy, and also prevents secondary problems such as excess hairballs in cats, tapeworms in both species, and skin infections if the problem is bad enough. To explain about tapeworms: tapeworm larvae live inside of a flea, the animal licks its fur and ingests the flea, the larvae are transferred to the dog or cat’s intestinal tract and the tapeworms develop in the intestines. Gross! They are easily treated, but can be avoided with regular flea preventative. We recommend flea prevention ALL YEAR LONG due to the lack of a cold winter in our area. If you suspect your pet has fleas or may have an allergy to fleas, please give us a call. Have a great summer; we hope to see you soon!

Dr. Jaime Kozelka
St. Francis Hospital for Animals