Allergy Intradermal Skin Testing

Make an Appointment

This information was reviewed and approved by Flavia Cecilia Lega Hoyte, MD (1/1/2025).

What is allergy intradermal skin testing?
How do you get ready for the test?
What is done during the allergy intradermal skin testing?
How long will the test take?
How do you get to your test?

 

What is allergy intradermal skin testing?

Your doctor has suggested you/your child have this test as part of the evaluation at National Jewish Health. Intradermal skin tests are done to help identify if you/your child are allergic and what you are allergic to.

How do you get ready for the test?

Please follow these directions when getting ready for this test. Check with your/your child's doctor before you stop the medicine. All antihistamines will affect the results of some of these tests and need to be stopped before the testing is done. If the medicine is not stopped before the test we will not be able to complete the test.

Stop these antihistamines for the length of time listed before your appointment at National Jewish Health.

  • Stop these oral antihistamines for 5 days before your appointment:
    • Allegra® (Fexofenadine)
    • Atarax®, Vistaril® (ydroxyzine)
    • Zyrtec® (Cetirizine)
  • Stop these oral medications for 3-4 days before your appointment:
    • Actifed®, Dimetapp® (Brompheniramine)
    • Benadryl® (Diphenhydramine)
    • Chlortrimeton® (Chlorpheniramine)
    • Claritin® (Loratadine)
    • Clarinex® (Desloratadine)
    • Phenergan® (Promethazine)
    • Tavist®, Antihist® (Clemastine)
    • Actifed®, Aller-Chlor®, Bromfed®, Drixoral®, Dura-tab®, Novafed-A®, Ornade®, Poly-Histine-D®,Trinalin® (Combination medicines)
    • Zyflo® (zileuton)
    • Tagamet® (cimetadine)
    • Zantac® (ranitidine)
    • Pepcid® (famotidine)
    • Axid® (nizatidine)
  • If you are taking an oral antihistamine that is not listed stop the medicine for 3-5 days before your appointment. If you are not sure if the medicine you are taking is an antihistamine, ask your doctor.  Some over-the-counter cold and flu medications contain an antihistamine, so be sure to read labels carefully for example, Tylenol Allergy and Tylenol Cold & Flu.
  • Stop these medications the night before your appointment:
    • Singulair® (montelukast)
    • Accolate® (zafirlukast)
  • Some psychiatric medications, including tricyclic antidepressants, as well as some sleep aides (examples: Tylenol® PM, Advil® PM and Nyquil™) can also affect the results of your skin testing. Let your doctor know if you are on any antidepressants or sleep aides before your test, but do not stop them without consulting the prescribing doctor.
  • Stop any supplements for 3 days. If you are concerned about doing so, please talk to your healthcare provider.
  • Do not apply lotions or creams to your back or forearms the day of your appointment.

Continue to take all your other medicine as you usually do.

What is done during the allergy intradermal skin testing?

When you have intradermal skin testing done, a small amount of each thing you may be allergic to (allergen) is injected under the skin. If you are allergic to an allergen, you will get a bump and redness where the allergen was injected. After a short time, each skin test reaction is measured for swelling and redness. A large enough skin reaction is a positive skin test. This means an allergy may exist to the allergen placed at that site. Your doctor or clinic provider will compare your skin test results with your history of symptoms o help determine if you are actually allergic to a particular allergen.

How long will the test take?

Intradermal skin testing often takes 30 to 40 minutes to complete.

 

How do you get to your test?

On the day of your scheduled test, please check in with admissions at the Center for Outpatient Health, and they will direct you to the skin testing area. Please arrive 15-20 minutes PRIOR to your scheduled appointment.

If you have questions, please call 303.398.1355.

PTE.002, Rev 4/06, 1/25

Make an Appointment