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Flea Allergy Dermatitis

Flea allergy dermatitis (FAD) is the leading cause of itching in dogs and cats. A bite from a single flea is enough to cause tremendous itching. Pets with FAD have a characteristic pattern of itchiness, hair loss, and secondary infections. Lesions develop along their backs extending to the tail and down the backs of the legs. Diagnosis of FAD is based on demonstrating the characteristic pattern of inflammation. Your veterinarian will check your pet for fleas and “flea dirt”, which appears as small black specks on your pet’s skin. The lack of fleas or flea dirt does not rule out FAD. All pets with FAD must be on topical therapy to prevent the fleas from biting. Oral flea preventives are helpful to break the flea cycle, however, they are not helpful as sole therapy in patients with FAD as the flea must bite the pet first to ingest the preventive. The home needs to be treated by an experienced professional exterminator, paying particular attention to your pet’s bedding and under furniture. The best treatment for fleas is prevention: year round monthly preventive topical applications.