A cute golden retriever laying down comfortably on his back

Logically, pets are itchy when they have fleas. But if your cat or dog is allergic to a flea’s saliva, they will become especially miserable. Known as flea allergy dermatitis, (or FAD), this condition causes pets to scratch and chew at the bites. Eventually, the pet’s skin becomes inflamed, and the dog or cat may develop sores and begin losing their fur. According to the Merck Veterinary Manual, flea allergy dermatitis is the most common skin problem of dogs in the United States.

Some pets have such an extreme reaction to flea bites that even just one little flea bite can cause a serious reaction. If the problem is not remedied, flea allergy dermatitis gets worse and worse. The serious itching and inflammation causes the pet to scratch and chew incessantly at the skin, damaging it as a result. What happens next? Secondary fungal or bacterial infections may develop. If this happens, your dog or cat will scratch or chew even more.

Signs

If your pet has a flea allergy, they will appear very uncomfortable in general. You may notice them scratching excessively, particularly during warm and humid weather when fleas are more active. If the climate where you live is always warm, your pet may have problems with fleas all year long.

According to medical director of Cornell University’s College of Veterinary Medicine, William Miller, if your pet is licking, chewing, rubbing or rolling, these are signs of flea allergy dermatitis. Miller warns that affected pets may develop a severe staph infection that could threaten the pet’s life if it spreads.

Known as hot spots, red, oozing lesions may develop in areas where your pet is scratching the most. They generally show up on dogs on their hind quarters and tail. In dogs with flea dermatitis, you may find their fur has thinned out along the base of the tail. In cats, large areas of hair may be scratched away. Tiny scabs may develop on much of her body, with the bulk of them appearing on her neck and rear end.

Your pet may develop an unpleasant odor if there is a secondary infection present. Affected skin may become darker and thicker in appearance. Look for a black debris at the base of the hair, which is flea feces.

Treatment

Your veterinarian may test your pet for allergies by conducting blood tests. Allergy shots or drops may be prescribed to treat their allergies. If your pet has developed a secondary infection from flea bites, antibiotics or an antifungal prescription may be required to heal them. To keep your pet from itching excessively, your veterinarian may prescribe steroids or an antihistamine.

The only effective way to treat flea dermatitis to eliminate fleas from their body and environment entirely. Flea treatments generally are safe, effective and easy to administer. When selecting a flea treatment, choose one that targets the flea eggs and larvae as well as the adult biting fleas. If you have more than one pet, you need to apply flea treatment to each one, even if they don’t show signs of a flea allergy. Your veterinarian may also recommend a daily or monthly pill to help control fleas.

Getting rid of all fleas in their environment is a necessary step. Get rid of old pet bedding, or wash it in hot water if you can. Vacuum your house and furniture often, throwing out the vacuum bag when you are finished. If the flea infestation is severe, consider having a pest control service spray your home every month, inside and outside.