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Flea allergy dermatitis (FAD)

Flea allergy dermatitis (FAD).


Flea allergy dermatitis is a hypersensitivity to flea saliva that may be caused by intermittent exposure to fleas.  A bite from a single flea will not have much effect on a normal dog, but those with FAD will react to the bite and become extremely itchy. Often the symptoms will be made much worse by the trauma the dog then inflicts upon itself.  


Symptoms of FAD

The initial reaction to a flea bite is:

-         Redness

-         Itching, chewing, licking.

-         Inflammation

Followed by:

-         Painful sores can appear over time

-         Hair loss

-         Crusting, yellow patches

The most commonly affected areas are the hindquarters and the area around the base of the tail. Other areas that are less commonly affected include the inner things, abdomen, and flanks. The picture below shows the areas most frequently affected:

My dog doesn’t have fleas, but he still seems to be reacting, why is this?

This is a common scenario and usually arises because fleas are still present in your dog’s environment.  Only complete eradication of the all the life stages of fleas will stop your dog’s FAD reaction. Eradication involves not only treating your dog with a good quality flea preventative, but also treatment of both the indoor and outdoor areas that your dog frequents with a flea spray that is effective against the immature life cycle stages. Flea sprays have traditionally contained pesticides, leaving some people with concerns about their safety in the home, but recently a new flea spray called Skoosh has become available that is non-toxic to both pets and owners.


If you think that yor dog may be suffering from FAD we recommend that you seek the advice of your vet. They will be able to discuss with you any changes you need to make to your flea prevention regime in order to minimise the effect of flea allergy dermititis on your dog. In more severe cases your dog may require treatment of the lesions caused by self trauma in order to get the symptoms under satisfactory control.