Suffering from allergies? Learn about skin-based and blood-based allergy testing and how Euphora Health can help.
Allergies are a very common problem that affect nearly 50 million people in the United States alone. Allergic reactions can present in a variety of ways, but often impact the eyes, nose, throat, and skin, and can sometimes be chronic and debilitating.
Each region of the world plays host to its own collection of allergens that may or may not plague local residents. In Austin, Texas, as with many other locations, it depends on the season.
Spring brings with it tree pollen–like Oak, Ash, and more–that drifts through the air and coats everything it falls on, while summer finds that grass pollen is its most problematic feature.
Weed pollen, from plants such as Ragweed, becomes a central issue in October and diminishes in November before Austin’s worst allergy season begins.
Winter presents the most intense allergy conditions and features the mountain cedar tree (Ashe Juniper) spreading its pollen grains for miles on the wind.
People dealing with constant and unpleasant allergy symptoms may seek to have some form of Allergen Testing performed and should ask their doctor what steps they should take.
The following is an overview of allergy testing: what it entails, what it looks at, and what options are available to those suffering from allergic reactions.
There are different types of tests that could be used to detect allergies, and each test has its own indications and contraindications to determine which test is the right one for a given individual.
The Role of Allergy Testing and the Diagnosing of Allergies
People who suffer from allergies typically experience some type of symptom in their body in the presence of an allergen.
When the body detects an allergen, the immune system produces a type of antibody called immunoglobulin E (IgE). The antibodies move throughout the system and communicate to cells to release a variety of chemicals that ultimately result in the reaction.
The types of IgE antibodies in the body determine what specifically causes an allergic reaction.
There are three factors that are relevant in diagnosing an IgE mediated allergic disorder.
- Using clinical history to identify the most likely allergen
- Using skin allergy testing or blood testing to demonstrate that an IgE specific to the allergen is the cause
- Determine that exposure to the allergen results in symptoms either by history or with a challenge procedure
There are two main types of tests for allergens: skin-based and blood-based tests.
Skin Testing Methods
The most common routes of skin testing for allergies include the prick/puncture method or the intradermal (under the skin) method.
Advantages of Skin-Based Testing
With skin-based testing, answers are obtained more rapidly, typically taking only 20 to 30 minutes as opposed to a blood test which can take multiple days. Skin-based testing is also less expensive and more sensitive, and can indicate the severity of the allergy based on the size of the reaction.
Who Should Not Have Skin-Based Allergy Testing?
Skin-based allergy testing isn’t right for everyone and should be carefully considered with a physician before any testing begins.
One of the biggest reasons to avoid this type of testing is found in patients who are at a high risk for anaphylaxis, a type of extreme allergic reaction that can result in long-term injury or death. Anaphylaxis most typically occurs in people with poorly controlled and severe asthma as well as those who have a history of strongly reacting to minute amounts of allergens.
The doctor and patient should consider if the risk is worth the benefit with skin-based allergy testing for patients with heart disease, frail older adults, and pregnant adults
Patients with the following skin conditions should not have skin-based allergy testing performed:
- Dermographism
- Acute or chronic urticaria
- Cutaneous mastocytosis
Prick/Puncture Method for Testing Allergies
Absent any reasons not to use this type of testing (such as those listed above), this is the most appropriate initial test.
Application of droplets of standardized allergens solution on the forearm or upper back, typically using a plastic device, places multiple allergens at once to test for reaction.
Patients usually feel nothing worse than a mild pinching feeling when this type of test is performed. A histamine control is also applied to test the body’s normal reaction to allergens.
After 20 minutes, the wheal (swelling) is measured to determine if the test is positive or negative. If it is equal to or larger than the wheal from the histamine control (or if it’s bigger than 3mm), it is considered a positive indication of allergic reaction.
Reactions from the test typically begin to resolve within 30 minutes, and over-the-counter antihistamine or cortisone creams may be used to help with itch or swelling symptoms.
Intradermal Method for Testing Allergies
Intradermal (under the skin) tests are much more sensitive than the prick/puncture testing method. This method does have some drawbacks, such as a higher rate of false positive reactions and higher rates of the test causing a systemic allergic reaction.
The test is performed by placing standardized allergen solutions (typically less concentrated than used in the prick/puncture method) under the skin using a needle and syringe.
In most situations, a wheal of 5mm or larger is considered a positive result.
Blood-Based Testing for Allergies (Also Known as In Vitro Testing)
There are IgE specific blood-based tests for food, environmental allergens (pollen, mold, animal allergens, dust mites, and cockroach allergens), insect venoms, latex, penicillin, and some occupational allergens.
These tests are performed by drawing blood, as is done for any other lab, and running IgE-based tests on the blood. As mentioned before, this is a type of antibody found in the blood when a patient’s body has reacted to an allergen.
Advantages of Blood-Based Testing
With blood-based allergy testing, there is no risk of allergic reaction occurring. Blood-based testing is not affected by any medication that the patient may be taking, and existing skin conditions that could cause variability in a test are not a concern.
Disadvantages of Blood-Based Testing
Blood-based allergy testing results are not as accurate as skin-based tests.
Positive test results show that a person has been sensitized (the body has created IgE molecules in response to allergen exposure), but sensitization alone is not an allergy. The body can create IgE in response to allergens but still not result in allergic symptoms.
The diagnosis of allergies depends on these findings in addition to allergic symptoms and signs of exposure to that allergen.
If a patient has a negative blood-based allergy test but also a medical history strongly suggestive of allergies, this does not exclude having an allergy.
Unvalidated Blood-Based Allergy Tests
IgG and IgG4 tests (typically used to evaluate for food allergies) do not predict true food hypersensitivity.
Getting Allergy Tested
Looking to get allergy tested?
Euphora Health is a Direct Primary Care (DPC) clinic that offers environmental allergy testing in Austin and Cedar Park.
DPC clinics like Euphora Health offer an alternative to insurance-based healthcare and provide a convenient system to start the process of allergy testing. Patients pay a monthly membership that includes unlimited, unrushed visits, virtual appointments, and 24/7 virtual access to their doctor.
Euphora Health is dedicated to learning each person’s full health history and giving personalized recommendations, and it is the perfect place to begin learning about allergy testing and how they can help.
Additionally, Euphora Health offers access to low-cost labs and prescriptions, such as those used to identify, monitor, and manage allergy symptoms.
Allergies can result in chronic discomfort and pain for a patient’s nose, eyes, throat, and skin. Environmental allergens can make life during certain seasons miserable and difficult. Euphora Health is here to help patients learn about their options and provide a path to knowledge and relief.
Learn more about Euphora Health’s services and pricing.
Allergy Services with Euphora Health
Through their clinic, members of Euphora Healthcare can receive skin-based environmental allergy testing for $87.
Testing for the following aerosolized (airborne) allergens is currently available:
- Mite Mix
- Cat
- Dog
- Cockroach Mix
- Mountain Cedar
- Mesquite
- Mulberry, White
- 9 Tree Mix (Alder, Ash, Birch, Elm, Hickory, Maple, Oak, Poplar, Sycamore)
- 7 Grass Mix (Fescue, June (KY Blue), Orchard, Perennial Rye, Red Top, Sweet Vernal, Timothy)
- Bermuda Grass
- Dock/Sorrel Mix
- Mugwort
- Nettle
- Russian Thistle
- 4 Weed Mix (Cocklebur, English Plantain, Lambs Quarters, Rough Pigweed)
- Ragweed Mix
- Alternaria
- Aspergillus
- Cladosporidium
- Bipolaris
- Penicillium
- Candida Albicans
Based on your personalized allergy testing, we can also guide you through the process of choosing over-the-counter treatment versus immunotherapy and even choosing between sublingual immunotherapy (allergy drops) and subcutaneous immunotherapy (allergy shots).
