What is My Pet Allergic To? Part 1 – FLEAS!

Fleas are itchy and annoying for all pets, but for a pet that is flea allergic, fleas can be intensely itchy and cause secondary skin infections. Yesterday, I saw a cat that was so itchy from her flea allergies that every time you pet her she would uncontrollably chatter and bite at the air or obsessively lick herself. She was just miserable!

Believe it or not, if your pet has allergies, you might hope that the allergy is to fleas rather than some other allergen. This is because compared to most types of allergies, you are more likely to be able to identify and possibly eliminate fleas. However, this does not necessarily mean that it will be easy!

What are the Signs of a Flea Allergy in Dogs and Cats?

Signs of a flea allergy include itching, scratching, licking, hairloss, and/or skin infections. Signs may be concentrated on the lower back, tail, and rear legs, but not necessarily. Cats will frequently get a condition known as miliary dermatitis which appears as many, small, crusty bumps on the skin. Keep in mind that the presence of these signs does not definitively diagnose a flea allergy, but are commonly seen with the condition.

But I Don’t See Fleas…

Often, when I ask an owner, they are confident they have never seen fleas. This is actually not unusual even when an animal has a severe flea infestation. Fleas are notoriously good at hiding. One tell-tale sign, that an animal has a flea problem, even if actual fleas have not been directly seen, is the presence of “flea dirt”. Flea dirt appears as tiny black specs within the hair coat or on the skin when the skin is combed against the grain. Flea dirt is actually flea feces or digested blood and if placed on a white towel and moistened, it will turn a red color.

What do I do to Treat Flea Allergies?

Even if there is no direct evidence of fleas, I still usually recommend taking steps to rule out the possibility of a flea allergy before delving into the often more complicated, time-consuming, and costly task of identifying other allergies. This is because the saliva from a flea bite can cause an allergic reaction for up to 6 weeks, long after the flea is dead and gone. So even if just one flea had the chance to bite, your pet could suffer the consequences for up to 6 weeks.

No flea product is a magic bubble that prevents fleas from biting if the animal is in a flea infested environment so keep this in mind when assessing your pet’s risk to flea exposure. Do you take your pet to the dog park regularly? Do you have stray cats that frequent your yard? These are questions to ask yourself when considering the possibility of potential flea exposure.

My first recommendation is usually to ensure adequate flea control by treating the affected animal, all animals in the household, the house itself, and the yard, as well as avoiding situations in which your pet may come in contact with fleas. Always use flea control products that are safe and effective for your pet. (We will discuss this in more detail in a later post.) If you can ensure that there is no chance of flea exposure for two months, there are no signs of infection, and your dog or cat is still itchy, we usually assume that flea allergy is not the primary problem. Always consult with your veterinarian about your pet’s specific medical conditions and treatment recommendations.