Inhalant allergy
or "atopy" is defined as an exaggerated response of the body to an inhaled
or absorbed substance that other people or animals tolerate just fine. The
classic example in people is hay fever, where when a person inhales pollens,
the result is runny eyes, sneezing and congestion. Inhalant allergy
in people is hereditary.
Inhalant allergy in the dog is similar in some ways to allergy in people
in that it is hereditary, but it is different in other ways. For example,
in dogs, the organ of the body that reacts to inhaled allergens is the skin.
Consequently, instead of sneezing and wheezing, dogs rub thair face, lick
their feet or just scratch all over. Also people tend to outgrow their allergies
whereas dogs grow into theirs; i.e., they get worse as they get older. In
addition to inhaling the allergen that results in itching and scratching,
there is some current proof that the allergen is absorbed across the skin
of non-haired areas of the body such as the feet.
As mentioned above, inhalant allergy in the dog is hereditary. Consequently,
we see it most often in the same breeds: Retrievers, Terriers, German Shepherd
Dogs, Dalmations, Shih Tzus, Border Collies, Collies, Poodles, Bichon Frises,
and mixes of all these breeds. Inhalant allergy starts anywhere from
6 months to 3 years of age. The main symptoms include itching of the
face and feet (most owners feel their dog licks its feet due to boredom, but
not so!), recurrent ear infections, recurrent bacterial or yeast skin infections,
and sometimes, but rarely, runny eyes and congestion. Sometimes a veterinarian
is able to pinpoint the class of allergen (trees, grasses or weeds) the dog
is allergic to according to when it starts to show symptoms. Some patients,
however, are itchy all year round and house dust mite allergy is most likely
the problem in these non-seasonally affected patients.
The veterinarian diagnoses allergy by taking history of
1. How old the patient was when the problem started (for example,
an 8 year old that just started itching is less likely to be atopic since
most atopic patients start at a young age).
2. The breed
3. Whether or not the patient is responsive to cortisone therapy.
The majority of inhalant allergic patients are cortisone responsive.
However, patients cannot be maintained on long term doses of cortisone
due to many deleterious side effects, such as diabetes, liver problems, cataracts,
osteoporosis,etc.
When a veterinarian suspects the patient is allergic, most often he/she
will refer the dog to a veterinary dermatologist for skin testing to determine
what the dog is allergic to. Skin or blood testing for inhalant allergy
is performed just as in people to determine what to put into the patients
desensitization injections. Desensitization injections are injections
given periodically composed of what the patient is allergic to in an attempt
to desensitze the patient over time. In dogs this usually takes 3-12
months and is approximately 75% successful. Since dogs with allergies
tend to get worse as they get older, desensitization may actually prevent
them from aquiring other allergies. Also, successful desensitization
prevents the patient from having to take steroids, which, as mentioned above,
can produce undesirable side effects.
Other treatments to help reduce the itching associated with inhalant allergy
include antihistamines and fatty acids. Unfortunately, antihistamines
are not as successful in relieving itching in some dogs as they are in relieving
symptoms of allery in people. Fatty acids which include Omega 3, 6 fatty
acids which can be found in fish oil. There has been reported a 20%
success rate when fatty acids are used together with antihistamines in attempting
to reduce allergy symptoms in dogs.
Most important to remember is that inhallant allergy is hereditary in the
dog and could be controlled by conscientious breeding. However since
some allergic patients do not show up with allergy untill 3 years old, they
could have already been breds numerous times producing many allergic offspring.
The number one breed I see in my practice with atopy is the Labrador
Retriever, possibly because it is currently the number one breed in the United
States. We have had Lab patients in as young as 4 months old that were
exibiting signs of inhallant allergy! Quite surprisingly most owners
do not realise that allergy is hereditary in dogs as it is in people. It
can be frustrating and expensive to treat a dog with inhallant allergy for
both the owner and veterinarian because there is no cure. As mentioned
above, desensitization is the safest option but can be very expensive and
is only effective 75% of the time. For pets whose owners cannot afford
skin testing and desensitization, most are destined to a life of cortisone
and deleterious consequences.
reprinted with kind permission from Dr Jeromin
http://www.purrfectpet.com/
The above information is simply informational. It's intent is not
to replace the advice of a veterinarian nor to assist you in making a diagnosis
of your pet. Please consult with your own veterinarian for confirmation of
any diagnosis. Your pets life may depend on it.
