Allergy testing in children: at what age and which test is useful

October 21, 2026about 15 minutesby mybody®x Editorial & Expert Team

An overview of allergy tests for children

In this article

At what age can children have an allergy test?

Sensitization can be tested even in infants and toddlers: according to the guideline, specific IgE is often measured in their blood instead of performing a skin test (Worm et al., 2021). The reason for testing is what matters: symptoms and a well-founded suspicion.

To clarify the terms: IgE stands for immunoglobulin E, or class E antibodies. The immune system produces them against certain proteins, such as those in food, and upon renewed contact they mediate the allergic reaction (Allergy Information Service, 2023). When these specific IgE antibodies are present, this is called allergic sensitization (Environmental Medicine Commission at the Robert Koch Institute, 2016).

Anyone who thinks young children cannot be tested will find the opposite in two sources. The guidelines on IgE-mediated food allergies explicitly list blood IgE testing as an alternative to skin testing for infants and toddlers (Worm et al., 2021). The Allergy Information Service (2023) says that doctors perform a blood test on younger children, as well as when a skin test cannot be performed.

For parents, another point is even more important, because a positive result can quickly sound like a diagnosis: an IgE level indicates sensitization, not a diagnosis. The Environmental Medicine Commission at the RKI (2016) describes sensitization as a prerequisite for an allergy, which can also be present without symptoms.

The Institute for Quality and Efficiency in Health Care (IQWiG, 2024) describes the blood test as an indication of an allergy, not proof of one. A positive result is significant only when considered alongside a clearly matching medical history or a positive provocation test (Worm et al., 2021). Our article explains what an allergy is in general: What is an allergy?

What allergy tests are available for children?

IQWiG (2024) describes three types of allergy tests, used one after another in a stepwise process. The guidelines place a particular emphasis on blood tests for children (Worm et al., 2021).

According to IQWiG (2024), the process follows this order after talking with the doctor:

• Skin test, such as the prick test: This is usually done first (IQWiG, 2024).
• Blood test: It is used when a skin test is difficult or too risky (IQWiG, 2024). According to IQWiG (2024), some allergens are also unavailable as ready-made solutions for skin testing.
• Provocation test: It only makes sense once skin or blood tests have failed to show clear results (IQWiG, 2024).

IQWiG (2024) describes these steps in general. The guidelines add what is given different weight in children, shifting the focus to measuring specific IgE in the blood (Worm et al., 2021). These accounts do not contradict each other. They describe the same approach from two perspectives: one for everyone and one focused on children.

A separate article covers the cost and process of an allergy test. This article focuses on children, and on which test is right at what age.

Not every reaction to a food is an allergy. Skin and blood tests look for IgE sensitization. The article on the difference between allergy and intolerance explains how these differ.

This sentence explains why a test result alone is not enough. Skin and blood tests show whether sensitization is present. On their own, they cannot tell you whether it causes symptoms.

Blood test or prick test: Which allergy test is right for children?

According to the Allergieinformationsdienst (2023), a doctor performs a blood test in younger children. In general, after talking with the doctor, the skin test is usually done first (IQWiG, 2024). Both show sensitization; neither alone shows an allergy.

You don’t decide between the two tests alone. The decision is made at the doctor’s office after discussing what you’ve observed. Factors include whether a skin test would be difficult or too risky for the child, and whether the allergen being tested for is available as a ready-made solution for the skin test (IQWiG, 2024).

Prick testing in children

Best for: the first step after talking to the doctor

Verdict: Generally the usual first test (IQWiG, 2024), but not the approach preferred by the guideline for children (Worm et al., 2021).

Blood test for specific IgE in children

Best for: infants and toddlers

Verdict: For children, this is the approach preferred by the guideline (Worm et al., 2021), with the same limitation as any IgE result.

For parents, what matters most afterward is how the result is interpreted. Both methods show sensitization, and the doctor assesses whether it fits the symptoms together with the patient’s history (Worm et al., 2021).

What does an IgE allergy test in children show, and what doesn’t it show?

An IgE test shows whether specific antibodies to a substance are present in the blood, meaning sensitization. As a rule of thumb, only half of sensitizations in the population are actually associated with symptoms (Worm et al., 2021).

An elevated result is therefore not automatically an allergy. According to IQWiG (2024), IgE antibodies can also be present in higher amounts in the blood without an allergy, for example in people who smoke or have a parasitic infection.

The level of the result also says little reliably about the severity of symptoms: the amount of allergy antibodies is not necessarily related to it (IQWiG, 2024). A high result therefore does not necessarily mean strong reactions.

If sensitization is present but there are no symptoms, it is called silent sensitization (Allergy Information Service, 2023). In a child without symptoms, a positive result may be just that: measurable, but without symptoms in everyday life.

For total IgE, the Allergieinformationsdienst (2019) gives a normal value of up to 100 IU/ml, or international units per milliliter of serum, for adults and children aged ten and older. Different values apply to children under ten, depending on their age (Allergieinformationsdienst, 2019). The information on your child's test report is what matters.

The article explains how these antibodies are produced in the first place: how an allergy develops.

The key facts and figures

Source for each figure in parentheses; the KiGGS data are from 2014 to 2017 (Thamm et al., 2018).

Which allergies are common in children?

In the Robert Koch Institute's KiGGS study, more than one in six children (16.1%) had at least one of three allergic diseases; hay fever was the most common (Thamm et al., 2018).

KiGGS is a cross-sectional study by the Robert Koch Institute involving children and adolescents in Germany (Thamm et al., 2018). The figures from the second wave are from 2014 to 2017 and indicate what percentage of 0- to 17-year-olds were affected in the past twelve months (Thamm et al., 2018).

The three conditions examined, each as a percentage of cases in the past twelve months:

• Hay fever: 8.8% (Thamm et al., 2018)
• Atopic dermatitis: 7.0% (Thamm et al., 2018)
• Bronchial asthma: 3.5% (Thamm et al., 2018)

These percentages have not changed significantly since the first KiGGS survey, which the authors interpret as stabilization at a high level (Thamm et al., 2018).

In addition, 37.1% of 3- to 17-year-olds were sensitized to a mix of multiple allergens (Thamm et al., 2018). The two percentages refer to different age groups and cannot be subtracted from each other. They only give a rough indication that sensitization is more widespread than allergic diseases (Thamm et al., 2018).

For food allergies, the guideline names these foods as the most common triggers in children and adolescents (Worm et al., 2021):

• Milk
• Chicken egg
• Soy
• Wheat
• Peanut
• Tree nuts

A 2004 study shows how common confirmed food allergies are: it found a food allergy confirmed by a challenge test in 4.2% of the children studied (Worm et al., 2021).

Not all allergies follow the same course. According to the guideline, peanut and tree nut allergies can persist into adulthood (Worm et al., 2021). The article Nut allergy or nut intolerance explains whether a reaction to nuts is an allergy or an intolerance.

When should a child be tested for allergies?

A test is useful if your child has symptoms and there is a justified suspicion that you discuss with your child’s pediatrician. The guideline advises against a broad screening test without a justified suspicion of a food allergy (Worm et al., 2021).

The reason for concern can look very different in everyday life. One child gets a rash after eating. Another sneezes every spring, or coughs as soon as they play with the cat at their grandparents’ house. These observations are the starting point, not the test.

In practice, the process begins with a conversation with the doctor, followed usually by the first test (IQWiG, 2024). For this conversation, it helps to note your observations: what your child ate or touched and what happened afterward.

Why not test just in case? Positive specific IgE only becomes significant when combined with a clearly matching medical history or a positive challenge test (Worm et al., 2021). Without symptoms, a result lacks precisely this medical history. Sensitization can also be present without symptoms occurring on contact with the allergen (Commission on Environmental Medicine at the RKI, 2016).

The AllergoCheck: What a home blood test can show

The mybody®x AllergoCheck (MYBODY Lab GmbH) measures IgE against 54 allergens in capillary blood, providing an indication of sensitization. It does not provide a diagnosis and is not intended as a screening test for people without symptoms.

The sample is collected at home: a finger prick is all that’s needed, and the tube is returned in the enclosed return bag. The sample is analyzed at a specialist laboratory in Germany, and the report is available as a PDF in the customer portal.

IgE is measured against 54 allergens, including those from pollen and foods. Cat and dog allergens are also included. A positive result for cat indicates sensitization, but not whether the coughing at the grandparents’ house is caused by it.

AllergoCheck is approved for ages 6 and up. This is the product’s age approval, not an age limit for allergy testing: for younger children, consult a pediatrician.

An elevated IgE level indicates sensitization, not necessarily symptoms. Some people have measurable antibodies but never react. Whether this develops into an allergy depends on the symptoms, and that is a matter for a doctor.

This test is intended for people with symptoms, not as a preventive screening test. Its purpose is to help you prepare for a conversation with your pediatrician: it provides an indication of sensitization that you can take with you. It does not replace that conversation, and the doctor decides whether to follow up with a skin test or a challenge test.

What are the limitations of allergy testing for children?

Skin and blood tests show sensitization, not a diagnosis, and the same applies to AllergoCheck. The sources for this guide also have limitations you should know about.

• The definition of sensitization comes from a position paper, not a study with original data (Kommission Umweltmedizin am RKI, 2016).
• IQWiG (2024) describes medical testing in which the blood sample is taken from a vein in the arm. AllergoCheck uses capillary blood from the finger.
• The guideline is from 2021 (Worm et al., 2021). The 4.2% rate of confirmed food allergies in children comes from a single study conducted in 2004 (Worm et al., 2021).
• Two pages from the Allergieinformationsdienst, one on skin tests and one on laboratory tests, are from 2019 (Allergieinformationsdienst, 2019).
• The KiGGS figures come from the summary of the study using data from 2014 to 2017 (Thamm et al., 2018). The rates of disease and sensitization refer to different age groups.
• AllergoCheck shows sensitization, not a diagnosis. Whether an allergy is present is determined by the symptoms and a conversation at the doctor’s office.

What should parents remember about allergy testing for children?

It doesn’t start with the test, but with what you observe in your child. You take these observations to the pediatrician’s office, where they choose between a skin test and a blood test; according to the guideline, for the youngest children the choice tends to be the blood test (Worm et al., 2021). A positive result indicates sensitization; it becomes significant only when there is a clearly matching medical history or a positive challenge test (Worm et al., 2021). Knowing this makes it easier to interpret any result calmly.

Frequently asked questions

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Sources

1. Environmental Medicine Commission at the Robert Koch Institute: Current status of the prevalence of allergies in Germany, Allergo Journal International (as of 2016) – rki.de; IQWiG: What allergy tests are available? (as of 2024) – gesundheitsinformation.de
2. Worm M. et al.: Update of the S2k guideline on IgE-mediated food allergies, Allergologie select (as of 2021) – europepmc.org
3. Allergy Information Service (Helmholtz Munich): Food allergies and allergy diagnosis (as of 2019 and 2023) – allergieinformationsdienst.de
4. Thamm R. et al. (KiGGS Wave 2, Robert Koch Institute): Allergic diseases in children and adolescents in Germany, Journal of Health Monitoring (as of 2018) – europepmc.org

The statements on sensitization and silent sensitization are based on [1] and [3]. The stepwise approach and the limitations of the blood test follow IQWiG in [1]. The guideline in [2] recommends preferring blood tests for children. The triggers and course of food allergies also come from [2]. The figures for allergic diseases come from [4], and the normal value for total IgE comes from [3]. Product information for AllergoCheck is from mybody®x, information as of 20.10.2026.