Blood Testing for Allergies Benefits, Types, and Clinical Considerations

About Blood Testing for Allergies

A blood test, also called a specific IgE test, is a powerful allergy diagnostic tool that measures the concentration of specific IgE antibodies in the blood. It can test for hundreds of allergic triggers, such as pollenmold, food, and animal dander. 

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 you are exposed to the specific allergen. The reverse may also be true. You may be sensitized to an allergen at any level. But if you don’t have symptoms when exposed to the allergen, you are not clinically allergic. The results of an allergy blood test, together with a detailed medical history and a physical examination, will help a healthcare provider develop a customized treatment plan for allergic symptoms.


How can blood testing help identify allergies? 

It’s vital to identify underlying allergic triggers. Track your symptoms.

Make the most of your appointment.

Talk to your healthcare provider about specific IgE blood testing.

Track your symptoms via this questionnaire. Then review your answers with your healthcare provider to decide if specific IgE blood testing is right for you. 

Benefits of Blood Testing for Allergies

There are many benefits to getting a specific IgE test.


Specific IgE blood testing gives consistently accurate results. An accurate determination of one or many allergen sensitizations will help healthcare providers prescribe appropriate medication, such as antihistamines or emergency medication, and create a custom plan for managing allergy symptoms. 

Easy and Accessible

Anyone experiencing allergy-like symptoms can receive specific IgE blood testing. That means anyone at any age can get a blood test. Tests are simple to perform and can be done irrespective of age, skin condition, antihistamine use, and pregnancy.1-4 

Safe and Quick

Unlike skin-prick testing, there's no risk that a blood test will trigger an allergic reaction. This is especially important if an individual is 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. Learn more about how specific IgE tests differ from other allergy testing options.

Wide Range

A specific IgE blood test can test for more than 500 whole allergens and mixes—such as pollens, foods, and animal dander—with a single blood sample. Identifying relevant allergens that together contribute to symptoms is a prerequisite for giving comprehensive allergen avoidance advice and keeping allergic individuals below their symptom threshold


Blood testing can detect various levels of allergen sensitization. An allergy blood test may also help a healthcare provider discover hidden risks, such as allergic reactions caused by cross-reactivity. Symptoms may have different originating allergen triggers or protein families and therefore require tailored treatment strategies. 

Types of Allergy Blood Tests

There are two types of specific IgE blood tests that can aid in the diagnosis of allergies:

  • Whole allergen tests can help identify allergic triggers and help rule an allergy in or out.5-7
  • Allergen component tests can help pinpoint the allergenic proteins that may be causing symptoms.8

Whole Allergen Testing

Specific IgE testing for whole allergens is used to help confirm a suspected allergy, to determine the cause of reactions, or to rule out an allergy altogether. 

Allergen Component Testing

Specific IgE testing for allergen components helps to identify the specific proteins that may cause reactions. So instead of just knowing that an individual is sensitized to peanuts, for example, a blood test can help pinpoint exactly which protein within the peanut may trigger a reaction. And knowing the specific protein can help a healthcare provider determine if there may be a risk for a more severe systemic reaction or a mild, localized reaction. 

Allergen components may help:

  1. Assess risk for systemic reactions. 
  2. Explain symptoms due to cross-reactivity. 
  3. Improve diagnostic accuracy. 

The Science of Allergies

Proteins and Allergies

Clinical Considerations: The Importance of Diagnostic Testing 

Allergy diagnosis based solely on physical examination, clinical observation, and patient history may result in an inaccurate or incomplete diagnosis. But adding diagnostic testing to aid in a differential diagnosis has been shown to increase confidence in diagnosis to 90 percent.9,10 

Diagnostic testing can also help in the following ways:11-13 

  • Improve the patient’s quality of life and productivity. 
  • Reduce costs associated with absenteeism. 
  • Optimize use of medication. 
  • Decrease unscheduled healthcare visits. 
  • Lower medication costs. 

Measurement of circulating IgE antibodies provides an objective assessment of sensitization to an allergen. In general, low IgE antibody levels indicate a low probability of clinical disease; whereas, high antibody levels to an allergen show good correlation with clinical disease.14 

Negative test results may enable healthcare providers to rule out IgE-mediated allergy altogether as a cause of a patient’s symptoms, better enabling them to steer the treatment path, medication, and management in the correct direction.9,10 


Understanding Which Protein Is the Problem 

The stability or lability of the protein and the amount of it contained within the allergen source are two highly important contributing factors. 

Stability: Protein families of components present in plants are ranked by their stability. The degree of stability is shared within a protein family. For instance, the families of storage proteins are very stable proteins. Proteins within the profilin and PR-10 families, on the other hand, are more labile proteins.15

Lability: Labile proteins are easily broken down by processing or cooking, or by enzymes in the saliva or gut. They will therefore primarily give rise to local reactions when ingested. Stable proteins, on the other hand, will reach the circulation in a more or less intact form and therefore potentially give rise to systemic reactions.15 

Some proteins with similar structures and functions across species are widely distributed in many allergen sources. These proteins may therefore cause cross-reactive IgE antibodies that bind to more than one allergen source. Understanding cross-reactions between species can help healthcare providers understand multiple sensitizations, such as those seen in Pollen Food Allergy Syndrome.


Adding diagnostic testing to aid in a differential diagnosis has been shown to increase confidence in diagnosis to 90 percent.9,10

Help your patients find answers.

When a patient’s symptoms and clinical presentation offer a wide range of diagnostic possibilities, such as an IgE-mediated allergy, test results can be a valuable tool in helping confirm the diagnosis. Together with the case history, serological testing can help bring clarity to an uncertain diagnosis and provide clear results that are easy to interpret and explain to patients. 

Take the next step.  

From ordering a specific IgE test to interpreting results, we have the resources you need to feel confident in your allergy diagnosis. 

How do you get tested for allergies? Consult with your healthcare provider today.

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.

Any healthcare provider can order a specific IgE blood test; it does not require seeing a specialist. Or you can request one directly from a lab. You have choices when it comes to how to get tested. 

Make the most of your appointment.

Answer our series of questions to help you better understand your symptoms. Then review your answers with your healthcare provider during an office visit to decide if specific IgE blood testing is right for you.

Tools for Understanding Allergies


Track allergy symptoms and prepare for a visit with a healthcare provider.

Learn about specific allergens, including common symptoms, management, and relief. 

Are you a healthcare provider? Get comprehensive information on hundreds of whole allergens and allergen components.

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  1. Siles RI, Hsieh FH. Clev Clin J Med. 2011;78(9):585-592.
  2. Bonnelykke K, Pipper CB, Bisgaard H. J Allergy Clin Immunol. 2008;121(3):646-651. 
  3. Belhocine W, et al. Pediatr Allergy Immunol. 2011;22:600-607.
  4. Bacharier LB, et al. Allergy. 2008;63(1):5-34. 
  5. Adapted from Duran-Tauleria E, Vignati G, Guedan MJ, et al. The utility of specific immunoglobulin E measurements in primary car. Allergy. 2004;59 Suppl 78:35-41.
  6. Adapted from Niggemann B, von Berg A, Bollrath C, et al. Safety and efficacy of a new extensively hydrolyzed formula for infants with cow’s milk protein. Pediatr Allergy Immunol. 2008;19:325-31. 
  7. Eigenmann PA, Atanaskovic-Markovic M O’B Hourihane J, et al. Testing children for allergies: why, how, who and when; an updated statement of the European Academy of Allergy and Clinical Immunology (EAACI) Section of Pediatrics and the EAACI-Clemens von Pirquet Foundation. Pediatr Allergy Immunol. 2013;24:195-209.
  8. Canonica GW, Ansotegui I, Pawankar R, et al. A WAO – ARIA - GA2 LEN consensus document on molecular-based allergy diagnostics. World Allergy Organ J. 2013;6:17. 
  9. Duran-Tauleria E, Vignati G, Guedan MJ, et al. The utility of specific immunoglobulin E measurements in primary care. Allergy. 2004;59 (Suppl 78):35-41.
  10. Niggemann B, Nilsson M, Friedrichs F. Paediatric allergy diagnosis in primary care is improved by invitro allergen specific IgE testing. Pediatr Allergy Immunol. 2008;19:325-331. 
  11. Welsh N, et al. The Benefits of Specific Immunoglobulin E Testing in the Primary Care Setting. J Am Pharm Assoc. 2006;46:627.
  12. Szeinbach SL, Williams B, Muntendam P, et al. Identification of allergic disease among users of antihistamines. J Manag Care Pharm. 2004; 10 (3): 234-238. 
  13. Szeinbach SL, Seoane-Vazquez EC, Beyer A, Williams PB. The impact of allergic rhinitis on work productivity. Prim Care Respir J. 2007;16(2):98-105.
  14. Yunginger JW, et al. J Allergy Clin Immunol. 2000;105(6pt1):1077-1084. 
  15. Molecular Allergology Users Guide. European Academy of Allergy and Clinical Immunology. 2016.