Allergy Testing: Purpose, Procedure, and Results

Allergies occur when your body’s immune system overreacts to something in your environment. For example, pollen, which is normally harmless, can cause your body to overreact and have a reaction. This overreaction can lead to allergy symptoms, like:

• a runny nose
• congestion
• sneezing
• blocked sinuses or sinus infections
• itchy, watery eyes

Allergy testing measures those reactions, however it’s possible for a person to have a positive allergy test to grass pollen, for example, but experience no symptoms whatsoever when outside sitting on grass. Additionally, a person can test positive to a food allergy while being able to freely eat that food with no reaction. Therefore, it’s important to go to a trained professional, preferably an allergist or specially trained Physician Assistant or Nurse Practitioner, to interpret the allergy testing results.  

How allergy testing is performed

There are a few types of ways to perform allergy testing. Allergies can be tested using skin testing, sometimes called a prick test or a scratch test, intradermal testing, also a skin-based allergy test, and a blood test. Allergists may use one of these methods or a combination. At Aspire Allergy & Sinus, the most common is to use a combination of a skin test and intradermal test to get the most accurate results.

How are people most commonly tested for allergies?

Allergy Skin Testing

Skin testing utilizes prick testing and intradermal testing. All skin testing involves putting small amounts of substances (animal dander, pollens, dust, molds, etc.) into the skin, and measuring the allergic response.

Patients should avoid using antihistamines, beta blockers and tricyclic antidepressants at least five days before allergy testing, or test results will not be accurate. Finally, patients that have glycerin sensitivity should not have skin testing because the allergens in the test are mixed with glycerin. Blood testing is still an option for patients with glycerin issues.

Prick Testing: Prick testing is conducted by an allergy clinician, and utilizes a multi-prong device, with no needles, which places 10 different allergens simultaneously into the skin. Allergy skin tests are not painful and do not produce bleeding. Some describe this type of testing like a hairbrush being pressed into the skin.

After cleaning the testing site with alcohol, six of these prick applicators will be applied to the skin on the forearms for a total of 58 allergens and two controls. Children usually have the prick test done on the back. After the prick test, it’s common to wait 20 minutes and then identify the results. A “positive” response causes redness and itching.

Intradermal Testing: Intradermal testing involves injecting a small amount of the suspected allergen under the surface of the skin. With prick or scratch testing, the allergens are placed on top of the skin, whereas with intradermal skin testing the allergen is directly inserted under the skin with the needle. If the results of a skin prick test are negative, your clinician will perform an intradermal test, as they tend to be more accurate. The injection site is examined about 15 minutes after the injections are made to see if there are signs of a reaction.

Allergy Blood Testing

Blood tests, sometimes called IgE antibody tests, are a common form of allergy testing but often produce false negatives for several environmental allergens. Because of this, we recommend skin testing for the patients that are able, especially if they are seeking immunotherapy, like allergy drops, allergy shots or ExACT Immunoplasty. We generally reserve blood testing for younger children, people who suffer from a skin condition or patients who are unable to stop taking beta blockers or other medications that could influence skin test results.

Once patients have undergone allergy testing, by either skin or blood testing, their prescription for treatment will be created based on the allergens that the individual patient reacted to. Patients can then begin their customized immunotherapy treatment plan with either sublingual allergy drops, allergy shots or ExACT Immunoplasty.

Is allergy testing safe?

Allergy skin testing is extremely safe. It’s very rare that allergy skin tests will cause a severe reaction, however it’s important to have your allergy test performed at an allergy clinic or medical center where in the event of an emergency, trained medical professionals can treat you.

The most common side effect of allergy skin testing is slightly swollen, red or itchy bumps on the skin. These are called wheals. Wheals may be more prominent during the test and then go away within an hour or two. In some instances, these wheals can last a couple of days.

Another side effect of allergy testing can be increased allergy symptoms, since we’ve just introduced your body to 58 allergens. Don’t worry though! We will provide you with an antihistamine upon leaving to manage any allergy symptoms that may arise from the allergy test.

On extremely rare occasions, an allergy test can cause an immediate and severe reaction that requires medical attention. Every Aspire Allergy & Sinus clinic is equipped with adequate medications, including epinephrine, and equipment to treat severe allergic reactions.

How to prepare for allergy testing

Before performing a skin test, you’ll be asked detailed questions about your medical health history, your allergy symptoms, how long you’ve had them and how you typically treat them. Medications can interfere with results, so we have a member of our nursing team go over any existing medications, vitamins or supplements you’re taking that may interfere with the test. We also ask that you refrain from taking any antihistamines for at least five days before your allergy test.

Common medications that can interfere with allergy testing:

• Over-the-counter allergy medications or antihistamines, such as loratadine (Claritin, Alavert), diphenhydramine (Benadryl), chlorpheniramine, cetirizine (Zyrtec Allergy) and fexofenadine (Allegra).
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• Prescription antihistamines, such as hydroxyzine (Vistaril).
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• Tricyclic antidepressants, such as nortriptyline (Pamelor) and desipramine (Norpramin).
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• Certain heartburn medications, such as cimetidine (Tagamet) and ranitidine.
• The asthma medication omalizumab (Xolair). This medication can disrupt test results for six months or longer even after you quit using it. For comparison, most medications affect results for days to weeks.

Allergy testing results

At Aspire Allergy & Sinus, you’ll have your allergy testing results before you leave the office. With the presentation of allergy testing results, you are always given several treatment plan options that are designed to suit a variety of needs and lifestyles. Most treatment plans include immunotherapy, like allergy drops, allergy shots, or ExACT Immunoplasty in addition to helpful tips or changes that can be made in the work or home environments to improve your allergies. With testing results that identify your allergens and a treatment plan, you’ll be able to greatly reduce or even eliminate your allergies for many years to come.

Get the Answers and the Relief You’ve Been Waiting For!

Most of our patients have suffered from their allergies for years and have been taking over the counter medications for years as well. Over the counter and even prescription antihistamines are solutions that we get used to, but are not long-term solutions, rather they only mask the allergy symptoms. We want you to live your life to the fullest, without allergies or sinus issues. Schedule your appointment with one of our allergy specialists, today!