An allergy blood test, also called a specific IgE test, measures the concentration of specific IgE antibodies in the blood. Any detectable level of specific IgE indicates a sensitization to a specific allergen. Even a low level of sensitization may be significant if it is associated with symptoms when exposed to the specific allergen. The reverse may also be true—a patient may be sensitized to an allergen at any level but if they don’t have symptoms when exposed to the allergen, they are not clinically allergic.
An allergy blood test is a powerful diagnostic tool that can test for hundreds of allergic triggers, such as pollen, mold, food, and animal dander. The results of your allergy blood test, together with your detailed medical history and a physical examination, will help your healthcare provider develop a customized treatment plan that's right for you.
Create and share your personalized assessment with the interactive My Symptom Profile tool.
Unlike skin-prick testing, there's no risk that a blood test will trigger an allergic reaction. This is especially important if you or your child are at a higher risk for a life-threatening, anaphylactic reaction. And for infants and young children, a single needle prick for a blood sample may be less traumatic than the repeated scratching of a skin-prick test.
A blood test may also help your healthcare provider discover hidden risks, such as allergic reactions caused by cross-reactivity.
How accurate are blood tests for allergies?
Skin-prick tests may be more sensitive than blood tests, however, both methods are considered accurate for diagnosing allergies.1 The accuracy of a blood test vs. a skin prick test can depend on a few factors:
Consistently gives accurate results
A blood test is quick and
simple and anyone at any age
can have a blood test
Can measure hundreds of
allergens with a single
blood sample
Detects various levels of allergen sensitization
The cost for a specific IgE blood test varies. Most health insurance plans cover a blood test option for allergies. To get a better idea of how much it would cost for you, contact your insurance company or take a look at these online provider options for associated cost(s) if you do not currently have health insurance.
Whole allergen blood tests
can help identify allergic triggers and help rule allergy in or out.3-5
Allergen component tests
can help pinpoint the allergenic proteins that may be causing your allergy symptoms.6
Watch this short video to learn more about each type.
Specific IgE testing for whole allergens is used to help confirm a suspected allergy, to determine the cause of your reactions, or to rule out an allergy altogether.
Specific IgE testing for allergen components helps to identify the specific proteins that may cause your reactions. So instead of just knowing that you're allergic to peanuts, an allergy blood test can pinpoint exactly which protein within the peanut may trigger your reaction. And knowing the specific protein to which you’re allergic can help your healthcare provider determine if you may be at risk for a more severe, systemic reaction or a mild, localized reaction.
1. Assess risk for systemic reactions.
2. Explain symptoms due to cross-reactivity.
3. Improve diagnostic accuracy.
A positive or negative specific IgE result for allergen components, along with your medical history, can give your healthcare provider important information for developing your personalized management plan. Certain components, or proteins, are associated with a higher risk of severe or systemic reaction than others. IgE levels for allergen components help estimate your level of risk for reaction by identifying the proteins to which you may react.
An allergy blood test provides a deeper understanding of your risk of reaction and could change the way your food allergy is managed. For example, a positive IgE test result to certain peanut proteins indicates that you are at risk for a systemic reaction, such as anaphylaxis, if peanuts are consumed. And a negative IgE test result to certain milk proteins may indicate that a milk-allergic child will not react to milk if baked, e.g., in cake or cookies.
By pinpointing the specific proteins that may be causing your symptoms, allergen components provide a more accurate assessment of your animal or pet dander allergy. A positive or negative IgE test result to allergen components, along with your medical history, can give your healthcare provider important information for developing your personalized management plan.
An allergy blood test provides a deeper understanding of your risk of reaction and could change the way your animal allergy is managed. For example, testing with allergen components can help differentiate between reactions that are caused by a specific species, like cats, and reactions caused by cross-reactive components. This information could impact your decision to get or keep a pet.
Cross-reactivity occurs when the proteins in one substance (e.g., pollen) are similar to the proteins in another (e.g., fruit and vegetables). And your body can’t tell the proteins apart, so your immune system can react to both. So while you may have a confirmed sensitization to, say, birch pollen, your body might recognize and react to similar proteins in an apple and thus trigger allergic symptoms.
Specific IgE testing for allergen components can help your healthcare provider identify the proteins that may be causing your reactions, which can make allergy management more effective.
By revealing your precise allergies, and determining which proteins you are sensitized to, allergy blood testing may be able to help confirm your triggers and help optimize your allergy management plan.
Not sure of your symptoms?
Create and share your personalized assessment with the interactive My Symptom Profile tool.
What can your My Symptom Profile tell you about allergies? Nothing, by itself. So resist the temptation to self-diagnose. Treating allergy symptoms with over-the-counter medications or other remedies without determining the cause could lead to more issues in the long run. When paired with testing, such as specific IgE blood testing for food or respiratory allergies, your My Symptom Profile can guide your healthcare provider in creating a customized trigger-management plan to help reduce exposure to suspected allergens.
Finished!
Download a PDF of your results to help guide your conversation and maximize your time with your healthcare provider.
What to know about specific IgE blood testing
What to know about specific IgE blood testing
What to know about specific IgE blood testing
What to know about specific IgE blood testing