Flea allergy dermatitis is an eczematous itchy skin disease of dogs and cats. For both of these domestic species, flea allergy dermatitis is the most common cause of skin disease. Affected animals develop allergic reactions to chemicals in flea saliva. Symptoms of this reaction include erythema (redness), papules (bumps), pustules (pus-filled bumps), and crusts (scabs). If severe, hair loss will occur in the affected area.

Dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...

s with flea allergy dermatitis often show hair loss and

eczema Dermatitis is inflammation of the Human skin, skin, typically characterized by itchiness, erythema, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become lichenification, thick ...

tous skin rash on the lower back, upper tail, neck, and down the back of the legs.

Cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...

s with flea allergy dermatitis may develop a variety of skin problems, including

feline eosinophilic granuloma Humans Human eosinophilic granuloma is characterized by abnormal proliferation of Langerhans cells (LCs). LCs are antigen-presenting cells derived from dendritic cells. In humans, eosinophilic granulomas are considered as a benign tumors that occur ...

miliary dermatitis In veterinary medicine, miliary dermatitis is a multifocal distribution of skin lesions, with no identifiable pattern. The term ''miliary'' means millet-like, as the papules on the coat of an affected cat feel similar to millet seeds. Causes Mil ...

, or self-inflicted

alopecia Hair loss, also known as alopecia or baldness, refers to a loss of hair from part of the head or body. Typically at least the head is involved. The severity of hair loss can vary from a small area to the entire body. Inflammation or scarri ...

from excessive grooming.

Cause

The flea found most commonly on both dogs and cats with a flea infestation is the cat flea, ''

Ctenocephalides felis The cat flea (scientific name ''Ctenocephalides felis'') is an extremely common parasitic insect whose principal host is the domestic cat, although a high proportion of the fleas found on dogs also belong to this species. This is despite the wide ...

''. Pets that develop flea allergy dermatitis have an allergic response to flea saliva injected during flea feeding. The itch associated with just one flea bite persists long after that flea is gone and leads to significant self-trauma.

Diagnosis

The diagnosis of flea allergy dermatitis is complicated by the grooming habits of pets. Cats in particular are very efficient at grooming out fleas, often removing any evidence of infestation. Fleas begin biting within 5 minutes of finding a host, and there are no flea treatments that kill fleas before biting occurs.

Treatment

The aim of treatment is to relieve the allergy-induced itch and to remove the fleas from the pet and its home environment. In some cases, secondary bacterial or yeast infections will also need treatment before the itching subsides. The administration of oral or topical flea prevention is also required to kill fleas currently on the animal. Environmental flea control includes using flea foggers or bombs, vacuuming, and treating pet bedding by washing on a hot cycle (over 60 degrees Celsius) in the washing machine. Many pets with flea allergy dermatitis may also have other allergies, such as allergies to food, contact allergies, and atopic dermatitis.

References

{{DEFAULTSORT:Flea Allergy Dermatitis Cat diseases Dog diseases

Cause

Diagnosis

Treatment

See also

References