What is skin testing?
Intradermal testing (IDT) or allergy skin testing is a tool that
aids the dermatologist in the selection of environmental allergens
(pollen, mold, mites, insects, dander) for subsequent immunotherapy
(allergen-specific allergy shots). This test followed by
tailor-made allergy shots is best performed after other
possibilities for the itchy skin disease have been excluded.
Veterinary IDT is similar to human allergy skin testing; however,
our patients need sedation and clipping. The side of the chest will
be shaved in the shape of a rectangle and small black Sharpie pen
dots will be put in a linear array on the shaved skin allowing us
to know where to make each injection. A panel of allergens is then
injected in the skin. The size of any developing wheals is
recorded. The entire procedure last approximately 30 minutes.
Importantly, this test is used for environmental allergies (atopic
dermatitis), not food-related allergies.
What medications need to be discontinued prior to skin
There are several medications prescribed for itchy skin that
will inhibit (wheals) on allergy skin testing. Please keep in mind
this is a rough guideline; individual cases may vary. Review the
drug withdrawal schedule below and discuss it with your primary
care veterinarian. Drugs are to be withdrawn under the advice and
discretion of your primary care veterinarian.
|Topical steroids (ears, skin, or eyes)
||15-30 days (2-4 weeks)
||30-60 days (4-8 weeks)
||70-84 days (10-12 weeks)
|Topical or oral antihistamines
||10-14 days (2 weeks)
|Fatty acid supplementation (if
||14-21 days (2-3 weeks)
||2-3 days (0.5 weeks)
||Case by case basis
What medications can I continue to give my pet prior to skin
Antibiotics, antifungals, flea prevention, heartworm prevention,
insulin, thyroid supplementation, heart medication, anti-seizure
medication, and ophthalmic cyclosporine/tacrolimus for dry eye can
be continued prior to any appointment or skin testing procedure.
Cool water baths with oatmeal can be used to help soothe the skin
and relieve itch up to 3 days before skin testing. Ears may be
flushed with a veterinarian-recommended flushing agent. Please
discuss what medications you should continue administering prior to
the appointment with your primary care veterinarian in the event
your pet has not yet been examined by the dermatologist.