Veterinary Dermatology Center
Robert G. Buerger, DVM, DACVD
Board-Certified Skin Disease Specialist

32 Mellor Avenue Suite B
Baltimore, Maryland USA   21228
410-788-8130
FAX 410-788-9007

www.Vderm.com
Pets with allergies:   An overview
Licking, chewing, scratching, and rubbing as well as  recurrent skin and ear
infections and  hot spots are common signs of allergies in pets.  The areas
commonly affected include the feet, belly, armpits, face, chin, ears, neck, rump, and
thighs, and secondary infections are common in these areas.   Other conditions
including those caused by parasitic and infectious organisms may result in similar
symptoms, so Dr. Buerger will  need to understand your pet's medical history and
perform a thorough dermatologic examination as well as a few basic tests to be
certain that allergy is indeed the problem.  Allergic symptoms can be year-round or
they can be seasonal (during particular seasons) depending upon which allergies
are present.  Allergies usually begin between 6 months and 3 years of age, but may
begin at any time.  Retrievers, terriers, and shepherds  are more likely to have
problems with allergies than other breeds.  The tendency to develop allergies runs
in families (as in people). Unlike people pets with allergies seldom "outgrow" them,
and their allergies commonly get worse and less responsive to treatments with each
passing year.  

The symptoms of allergy can often be improved or controlled with one or more of
the following: antihistamines, cortisone (i.e. prednisone) tablets, Apoquel® tablets,
Atopica® capsules, Cytopoint® injections, frequent shampoos, flea preventatives,
and in some instances restricted hypoallergenic diets.   It's also important to
maintain a clean and matt-free coat.  These are acceptable means of control if the
allergic symptoms are seasonal or of  short duration (lone to several months) and
as long as the treatments do not result in severe or objectionable side effects.  
Allergy testing and more specific therapy with allergy injections should be
considered if:  (1) the problem is prolonged (especially if it is year-round); (2) the
problem is not adequately controlled with symptomatic treatments; (3) the treatment
necessitates prolonged or repeated courses of cortisone drugs or antibiotics; or (4)
the treatments cause severe or objectionable side effects.

If you have any questions or concerns please discuss them with Dr. Buerger during
your pet's next appointment.

Allergy skin testing:   Questions and Answers
What does allergy testing entail?
Intradermal allergy testing involves making 65 small test injections into a patch
shaved on the side of the chest.  This is often done while your pet is sedated and
while you wait (usually takes about 30 minutes). Redness and/or swelling at the
injection sites allows us to determine which allergies are present.  This test helps to
diagnose environmental allergies.  It does not diagnose food allergies.  
Food
allergies can only be diagnosed and controlled with a strict hypoallergenic
diet.  

What is the benefit of allergy skin testing?
After the cause of the allergy has been determined, it can then be treated  
specifically with an injectable allergy vaccine or in some cases with oral allergy
drops (sublingual immunotherapy) that is formulated based on the allergy test
results.   

Are allergies to flea bites or to food allergies treated with allergy injections?
Unfortunately, injections for flea bite allergies do not work in most instances.  Strict
flea control measures must be implemented for allergic pets and for other pets in
the home.  Also food allergies can only be diagnosed and controlled with  a strict
hypoallergenic diet.  

Are there alternatives to allergy skin testing?
If skin testing is not performed it is still usually possible to control the symptoms of
the allergy with medications although there may be significant side effects.  The
long-term use of cortisone drugs in particular may result in adverse side effects.  

Blood allergy testing may be recommended in place of skin testing under certain
conditions.  Concurrent medical conditions or other skin issues may prompt a
recommendation to perform blood allergy testing first.

When is the best time to skin test?
The skin test can be performed anytime, but for some seasonally allergic pets the
best results may be obtained near the end of the allergy season (often in the early
fall months).

How often are allergy injections given?
In the initial stages the injections are given on alternate days.  Gradually the length
of time between the injections increases to once every three weeks, but for some
pets the injection schedule may need to be modified.  
Allergy injections will
likely be necessary for the life of the patient: They help control symptoms,
but they don’t cure
allergies.   

Who gives the allergy injections?
With guidance most owners can learn how to give the injections. The technique is
simple, and adverse reactions to the allergy vaccine are very rare.  Alternatively we
can give the injections here in the office or perhaps your regular veterinarian may
be able to help you.  

Can allergens by given by mouth instead of by injection?
Injections of allergens have been used to control allergies for many decades, and
studies have demonstrated their usefulness. Oral allergy drops (so-called
sublingual immunotherapy [SLIT]) is another newer option to help control allergies.  
A few studies have shown that they are also effective in most patients, and we can
present this as an alternative to allergy injections.

Other than the obvious differences in the route of administration what are
the major differences between allergy injections and oral allergy drops?
While allergy injections are generally administered every 3 weeks oral
allergy drops will need to be administered twice daily
.  In either case the
treatments will need to continue life-long (since it’s a means of control...not a
cure).  In some cases Dr. Buerger may make changes to the administration
schedule.

How long does it take to see benefit from the allergy injections?
While some pets improve within weeks most pets require 3 to 9 months of therapy
to see benefit.  Some may take one to two years to show improvement.  The
response to the treatment may be total or it may be partial.  If it is partial other
medications may still be necessary to help control some of the symptoms.     
During the first few months of the injection program many pets will require additional
medications to help with comfort.  As the allergy injections take effect,
and as the symptoms subside these medications should be gradually weaned.   

Approximately 25% of allergic pets do not respond to the allergy injections.

How is my pet prepared for the allergy skin test?
Cortisone tablets such as prednisone, Temaril-P, Vetalog, or Medrol  must be
stopped at least 4 weeks prior to allergy testing (longer in some instances).  The
waiting period may be considerably longer if the cortisone has been given by
injection.  Consult your veterinarian before stopping a cortisone as a gradual
withdrawal may be recommended.  Cortisone-containing eye and ear drops should
also be stopped 7-10 days prior to the test if possible. Antihistamines such as
Benadryl, hydroxyzine, Zyrtec, and chlorpheniramine must be stopped at least 14
days prior to allergy testing. Apoquel®, Atopica®, and Cytopoint®  do not have to
be stopped as these will not affect test results.  

Also, your  pet should not be fed within 12 hours of the skin test, and water should
be withheld for 2 hours before the test.  No tranquilizer should be given without first
checking with Dr. Buerger.

What is the cost of allergy skin testing?
The total cost of allergy testing is usually in the range of $790-1190+ which
includes the first set of treatment allergens.  This is a wide range because in some
cases additional laboratory tests may be indicated, sedation is often necessary,
additional medications may be necessary, and some pets will require two sets of
treatment allergens (if they have a large number of allergies).

Once the results are known, what are the long-term maintenance costs
associated with giving allergy injections or oral allergy drops?
Refill vials of prescription injectable allergens are $249 and last about 6 months
with the standard injection schedule (
given every 3 weeks...life-long).  The cost
of syringes is extra.  The cost of the allergy vaccine may be  higher for certain
types of allergies.

Refills of oral allergy drops are $259 and last about 5 months with the standard
schedule (
given twice daily...life-long).

If you have any questions, please ask your veterinarian or Dr. Buerger during your
pet's next appointment.
                                                 ©1/2017
Allergies and Allergy Skin Testing