Allergy Prick Skin Testing

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

Allergy Prick Skin Testing

You are being tested to allergens which may include environmental allergens, foods, stinging insects, PCN and anesthetics.

Additional testing cannot be completed without provider approval PRIOR to your scheduled test. Please call your provider ahead of time if you have questions regarding additional testing.

What is allergy prick skin testing?

You are being tested to allergens which may include environmental allergens, foods, stinging insects, PCN and anesthetics.

Additional testing cannot be completed without provider approval PRIOR to your scheduled test. Please call your provider ahead of time if you have questions regarding additional testing.

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 these tests and need to be stopped before the testing is completed. If the medicine is not stopped before the test we will not be able to get an accurate result.

Stop these antihistamines for the length of time listed before your appointment at National Jewish Health.
- Stop these oral antihistamines for 5 daysbefore your appointment:
  - Atarax®, Vistaril® (hydroxyzine)
  - Claritin® (loratadine), Allegra® (fexofenadine) Clarinex® (desloratadine)
  - ChlorTrimeton® (chlorpheniramine)
  - Dimetapp® (brompheniramine)
  - Phenergan® (promethazine)
  - Tavist®, Antihist®, Dayhist® (clemastine)
  - Xyzal (levocetirizine)
  - Zyrtec® (cetirizine)
  - Combination medicines: Actifed®, Aller-Chlor®, Bromfed®, Drixoral®, Dura-tab®, Novafed-A®, Ornade®, Poly-Histine-D®, Trinalin®
Stop these oral medications for 3 daysbefore your appointment:
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:
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.

Continue to take all your other medication as you usually do. Inhaled, nasal and oral glucocorticoids (steroids) will not interfere with the results of your skin testing.
Do not apply lotions or creams to your back or forearms the day of your appointment.

What is done during the allergy prick skin testing?

When you have prick skin testing done, a small amount of each thing you may be allergic to (allergen) is placed on the skin (usually your back). The skin is then pricked. If you are allergic to an allergen, you will get a bump and redness where the skin is pricked. 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 will compare your prick skin test results with your history of symptoms.

How long will the test take?

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

How do you get to your allergy prick skin 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-001, rev 1/13, 1/18, 1/25