All Pets Veterinary Clinic
It is estimated that at least one in five dogs in the United States suffers from
some sort of allergy. That number may be on the rise. This article will discuss
the signs, diagnosis, and treatment of allergic conditions in pets.
What animals are typically affected by allergies? For the most part, allergies
will tend to develop in the early years of a petís life. 85% of all allergic animals
are first diagnosed when they are under 3 years old. Studies have determined that
many allergies are inherited. There are many breeds that have demonstrated a strong
breed predisposition for allergies. Some of these breeds include Terriers, Irish Setters,
Beagles, English Setters, Lhasa Apsos, Pugs, Labs, and Miniature Schnauzers. Other breeds
not mentioned here, as well as mixed breeds, can also have problems with allergies.
Neither sex is more affected by allergies than the other.
What are the signs of allergies? When most people think about the signs and
symptoms of allergies they think about runny eyes, a stuffy nose, and sneezing. While
these things can all happen in animals, they are NOT the typical signs associated with
allergies. The most common manifestation of allergies in pets is itching and scratching.
As a result of this itching and scratching animals may have reddened or thickened skin,
hair loss, and scabs or crusts. Animals that have problems with allergies may also lick
or chew excessively at their feet. In white animals this can cause a brownish
discoloration of the hair on the paws. The most common areas affected include the head,
face, ears, base of the tail, and the feet or paws. In severe cases, the signs may be
generalized or all over the animals body. Allergic animals may demonstrate signs at
certain times of the year or throughout the whole year, depending on what they are
What are some of the things animals are allergic too? Animals can be allergic
to almost anything, inhaled, ingested, or contacted, including but not limited to pollens,
molds, grasses, weeds, trees, and foods. Flea allergy is the most
common allergy seen in pets. The bite of one flea is enough to start an allergic
animal itching and scratching.
How are allergies in pets diagnosed?
1. History and physical exam. While certain information on frequency and location
of itching and scratching and the general appearance of an affected animal can suggest
an allergy problem, this alone CANNOT diagnose an allergy. This is because there are
many other conditions that can cause skin problems that may appear to be allergies.
Some of these conditions include external parasite problems, fungal infections, autoimmune
disease, and bacterial infections.
2. Preliminary testing. In order to assure that your pet does not have an underlying
condition that is causing allergy-like signs and symptoms, it may be necessary to perform
some simple tests. A skin scrape may be done to look for sarcoptic mange or demodex.
These are two external parasites that can cause hair loss and itching. A fungal culture
may be done to determine that your pet is not suffering from an external fungal infection.
Skin cytology may confirm the presence of a primary or secondary yeast or bacterial infection.
A skin biopsy may be done to determine how the animalís skin is reacting at a microscopic
level. It will also determine if your pet is suffering from pemphigus, a disease in
which the bodyís immune system "attacks" the skin. If these tests are all negative,
other tests may be done to determine what your pet is allergic to.
3. Allergy testing. There are two options for definitively determining what your
pet is allergic to. The first is intradermal skin testing. With this method, your pet
is sedated and some hair is clipped. A small injection of each of the items being tested
will be injected into the skin. After a designated amount of time, the veterinarian will
look at the reaction, if any, that the animal had to the item injected. The second
option is serology. With this method, a blood sample will be drawn from your pet.
This blood will be sent off to a lab that will use the blood to determine what items your
pet is allergic to.
4. Diet trial. Since intradermal skin testing and serology cannot accurately determine
if an animal is allergic to a certain food component, a diet trial may be done. In a diet
trial, the animal will be switched to a food with a new protein source. The most common
protein sources that cause problems in dogs and cats include beef, chicken, turkey, corn,
soy, wheat, and egg, among others. Thus, the special diet must not contain these components.
If the signs resolve while on the special diet and reoccur when the original diet is fed,
a food allergy can be suspected. In some instances, multiple food trials may be necesssary.
How are allegies treated? There are two general ways to treat allergies. The
first is indirectly or symptomatically. With indirect treatment options you only treat
the signs of the allergies--you strive to make the animal more comfortable, short term,
by suppressing the itching and scratching. Nothing is actually done to solve the allergy
problem with indirect treatment methods. The second is directly. With direct treatment
you aim for the root of the problem--you strive to make the animal more comfortable, long
term, by altering the way the body responds to the things it is allergic to.
Indirect methods. Some of the things used to treat allergies indirectly include steroids,
antihistamines, fatty acid supplements, and "anti-itch" shampoos and rinses. Probably
the most common thing used to help allergy prone pets is steroids. While these are highly
effective for controlling allergies, there are many side effects. These side effects
include, but are not limited to, increased susceptibility to infections, hair loss, dry
and poor quality hair coat, poor skin elasticity, increased panting, increased appetite,
increased water consumption, increased urination, stomach ulcers, and liver and adrenal gland
problems. It is very important to realize that while steroids may make your pet feel
better, they should not be relied upon for long term allergy treatment or control because
of the problems they can cause. Newer products such as Atopica and Apoquel have shown
promise in decreasing the itch level in allergic patients.
Direct methods. Currently, there are only two things that can directly be done to treat
allergies. The first is to remove the offending items from the petís environment. This
is relatively easily done for things like fleas and wool, but not so easily done for
things like mold and pollen. The second thing that can be done to directly treat allergies
is to do hyposensitizaion therapy or "allergy shots." Through hyposensitization, a
series of injections containing the different things the pet is allergic to, is
administered over several months. By doing this, you enable the petís immune system to
become familiar with the things that it is allergic to. Thus, with successful
hyposensitization you can hopefully get the animal to no longer be sensitive to the
things it was previously allergic to. This is currently the safest way to treat allergies
Non prescription products that may help with allergies are available at our online store
(see link below) and include: allerspray, dihphenhydramine, allegroom shampoo, allermyl spray
or shampoo, aloe oatmeal shampoo and conditioner, dermal soothe shampoo and conditioner,
dermallay shampoo and spray, episoothe shampoo and cream rinse, relief cream rinse and
shampoo, omegaderm oral supplement, 3V caps, AllerG-3 capsules, and derm caps.
The information provided is for educational purposes only and is not
intended to take the place of your regular veterinarian. Please do not hesitate
to contact your regular veterinarian if you have questions regarding your pet.
Karen Blakeley, DVM, MPH
12 March 2016