We all know what a pain in the rear a flea infestation can be to us and our animals. But did you realize that some pets are actually allergic to fleas? Both dogs and cats can be flea allergic, resulting in severe itching and/or obsessive grooming. Dogs may experience loss of hair, redness, or hotspot-like sores, particularly over the rump and tail. Cats often have hair loss, especially over the back, and may have tiny scabby crusts.


When these pets are bitten by a flea, they are exposed to the parasite’s saliva. Some pets are very allergic and develop a reaction similar to a mosquito bite. A “normal” pet is minimally affected by this, but pets with flea allergies can become very miserable very quickly. In fact, even just one bite may not be tolerated.

Flea allergies are often diagnosed by a simple physical examination. Pets with flea allergies have a characteristic appearance. Sometimes live fleas or flea dirt is found on the pet, although some animals are very effective at removing all “evidence” while grooming themselves.


Flea allergies are serious business, but luckily they are easily treated. The goal is simple: reduce the number of flea bites. Fortunately there are many very effective flea preventatives on the market. Discuss with your veterinarian which product is most appropriate for your pet. Remember that all pets in the household need to be treated in order to decrease the pest burden in the home. Some flea allergic pets that are having a flare-up may also need additional help in the form of anti-inflammatory medications or antibiotics. It is best to keep these animals on a quality flea preventative year-round in order to prevent severe reactions.