Flea allergy dermatitis is the most common allergy
in dogs and cats and is caused by flea bites.
It is a very itchy disease and predisposes to
the development of secondary skin infections.
Adult fleas are blood-sucking parasites that require
a host, such as a dog or cat, for protection,
food and survival. When a flea bites an animal,
a variety of irritating and/or allergy-causing
substances from its saliva are injected into the
skin. Pets are not allergic to the fleas themselves.
They are allergic to the protein in the flea saliva
when the fleas bite the pet.
In
an allergic pet, the bite of only one flea may
cause a serious problem and the pet will itch
for over five days. Extensive skin damage may
result from the pet's biting, licking and scratching.
Though flea bite allergy can be treated, it often
recurs since:
a)
Flea eggs may hatch up to 1 year after being deposited
in the environment.
b)
Most of the flea's life cycle occurs off the pet.
c)
Your pet's environment may be contaminated with
fleas.
d)
Even an occasional flea bite can trigger the allergic
reaction.
Pets
with flea allergy have very few fleas because
they are so itchy, they groom themselves excessively,
eliminating any evidence of fleas. However, a
couple of flea bites every two weeks are sufficient
to make a flea allergic pet itchy all the time.
Fleas
are bloodsucking insects with a life span of 6
to 12 months. This life span is influenced by
environmental conditions and can vary from two
to three weeks up to a year. The adult flea spends
most of its life on the host, while the immature
stages (eggs) are found in the environment. The
worst time of the year for fleas is from spring
to late fall. Warmer climates may experience a
more prolonged flea season. Animals residing in
southern states may have fleas and the resulting
allergic reaction year round.
The
abdomen and rump are the most commonly affected
areas in the dog. These itchy areas may develop
oozing scabs. Cats, on the other hand, typically
overgroom; they may have hair loss but not develop
skin lesions.
Symptoms
- Severe
itching
- Chewing
and biting of the tail, rump, back legs and
occasionally front legs
- Oozing
lesions (lick granuloma) from chewing
- Hot
spots on the hips or face, which is severe
skin damage from scratching
- Excessive
hair loss
- Small
red papules with reddish-brown crusts
Diagnosis
Flea
allergy dermatitis is a common cause of itchiness
and scratching in pets, but other medical problems
can lead to similar symptoms. Other disorders
that must be excluded are:
- Food
allergy
- Atopy
- Trauma
or other cause of local skin irritation
- Sarcoptic
mange
- Cheyletiellosis
(a mite infestation)
- Primary
keratinization defects
Diagnosis
of a flea allergy is made based on pet's history,
examination of the skin, presence of fleas, and
response to treatment. Fleas may be seen crawling
on the dog or cat. Fleas in hiding may be hard
to spot, so veterinarians examine affected areas
looking for flea excrement, also known as flea
dirt, which looks like small, black to rust colored,
comma-shaped dandruff. Unfortunately the absence
of fleas or flea dirt does not rule out flea allergies.
To confirm that the particles found on a pet are
flea dirt, place the substance on a wet paper
towel. Flea dirt will turn a red or reddish-brown
color signifying digested blood.
Some
pets may have more than one medical problem. For
example, scratching or biting due to flea irritation
can cause a “hot spot” (acute moist dermatitis)
and secondary bacterial skin infection (pyoderma)
can follow.
Preventative
Care
- Prevention
of flea bites. The most important part of
treatment is preventing flea bites with aggressive
flea control on your pet and in the environment.
- Treatment
of secondary skin infections. Antibiotics
and antifungal drugs may be necessary to treat
secondary skin infections triggered by the
flea allergy.
- Breaking
the itch cycle. If your pet is intensely itchy,
a short course of steroids may be necessary
to break the itch cycle and make your pet
more comfortable.
- Frequent
bathing.
-
All
bedding and rugs must be cleaned to make
sure that there are no flea larvae. Frequent
vacuuming and carpet cleaning strategies
can help remove eggs and larvae from the
pet’s indoor environment. Professional cleaning
or exterminating service in difficult cases
can be very helpful.
Advantage
flea control for cats and dogs for common
allergies to fleas.
Use
an effective safe flea control product on your
pet on a regular basis. Flea Preventive are the
simplest way to treat animals. If your pet has
flea allergies, a topical adult Flea Preventive
is better than an oral product. The goal is to
kill adults before they bite so the animal is
not exposed to saliva.
See
your veterinarian promptly if your pet develops
acute skin lesions (acute moist dermatitis) as
a result of biting or scratching at fleas. Frequent
grooming of your pet with a “flea comb” may be
helpful to remove fleas.
____________The
pup stops here! 
