Flea bite dermatitis is an allergy to flea saliva. It doesn't take a severe flea infestation to elicit a reaction. It takes just one flea bite. When the flea bites your dog, it injects saliva into him. The saliva contains various antigens that causes a reaction in some dogs. Even if you don't see any fleas or flea dirt, there are signs of flea bite dermatitis signs that you may notice.
At first, you may not think anything about itching, scratching and nibbling at the skin, but you will if it become excessive. Your pet may start rubbing himself on furniture and rolling over to scratch his back on the carpet. The skin may become red and swollen, and you may notice scabs on the lower back and by the base of the tail where open wounds are trying to heal. Because of the excess scratching, your dog may suffer hair loss. Hair loss generally occurs at the base of the tail, back legs and the middle back area.
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