A food allergy occurs when the body mistakes a specific food as harmful. This leads the immune system to overreact and results in reactions which can range from mild to severe. Remember, the immune system’s job is to protect the body by identifying potential threats and fighting them off. In most cases, the immune system does a good job in identifying true threats. For a child with allergies, however, the immune system mistakenly identifies an otherwise safe food as a threat. Click here for more background on food allergies in general.

As a parent of a child with food allergies, it is also helpful to know the most common food allergens, as well as the difference between a food allergy and a food intolerance. 

Being familiar with the common symptoms of an allergic reaction is also important. These include:

Food allergies are common. About 1 in 13 children (8%) in the United States have a food allergy. That means, in a daycare class of 20 children, 1-2 will, on average, have a food allergy. In addition, among those with a food allergy, 40% are allergic to more than one food.

‍Food allergies have also been rising in prevalence for the past two decades. This means that parents today face a higher likelihood of food allergy in their children than parents of prior generations. 

The nine most common allergens account for over 90% of reactions. Here they are by prevalence:

It's important to note that food allergy risk varies by age, with infants and young children at higher risk for certain allergies. For instance, 8.9% of infants have an egg allergy, much higher than the average rate among all children. And, 2-3% of children under three years old have a milk allergy.

Your child's immune system develops rapidly until around age 5. Since food allergies are a function of a person’s immune system, whether your child has food allergies and how severe they are can change during this period. 

How likely your child will outgrow their food allergy can depend on which foods they are allergic to as well. According to this clinical review, milk and egg allergies are more likely to be outgrown as children age while peanut, tree nut, sesame, fish, and shellfish allergies are more likely to persist into adulthood.

However, it is difficult to predict specifically how your child’s immune system will change over the years. While they have a food allergy, proper management and treatment remain critical. You can work with your allergist to monitor your child’s allergy, for instance through regular testing or food challenges, in order to determine if the allergy has been outgrown or not.

There is no single approach to treating food allergies. How you and your family decide to manage a food allergy will depend on multiple factors, such as the severity of your child’s allergy, lifestyle constraints, availability of care, and other preferences. Below is an overview of potential options. The development of a treatment plan, which may include one or more of the approaches described below, should take place in conversation with your doctor.

Strict avoidance is the treatment approach that people are usually most familiar with. Just as it sounds, it entails completely avoiding the allergen. This approach requires:

Strict avoidance is a common approach and, for decades, was the only option. Strict avoidance is frequently used as “standard of care” and provides the foundation of food allergy management.

Certain children with milk or egg allergies may be candidates for a food ladder approach. This approach builds on the fact that many children who are allergic to milk or egg in their “pure” or less-cooked form can tolerate these same foods when they’ve been cooked. This is because the cooking process breaks down the proteins in ways that make them less likely to trigger an allergic reaction. As always, discuss with your allergist whether a food ladder approach is appropriate for your child.

‍While the specifics can vary, a food ladder approach generally entails starting with the most easily tolerated, most cooked versions of the allergen and gradually exposing your child to less processed forms of the allergen. In this way, your child will “climb” the food ladder to gain increasing tolerance to these allergens. Children usually require 1-3 months of regular exposure to each “rung” of the ladder before progressing. This process can be done at home in consultation with an allergist and involves common foods, such as baked goods (e.g., muffins), pancakes, egg noodles, or pizza. (Here is an example of a food ladder.)

The food ladder approach is only applicable to some children with milk and egg allergies. The goal is to increase your child’s tolerance to these foods and has the added benefit of being done at home, rather than in a clinical setting.

While research on oral immunotherapy has been around since the turn of the century, widespread clinical use of this treatment approach began about a decade ago, making it a relatively newer option compared to strict avoidance. It also is not suitable for all babies and may not be offered by all clinics, but years of experience have shown it to be both safe and effective. 

Like the food ladder approach, OIT involves gradually exposing your child to the allergen in order to increase their tolerance. Unlike the food ladder approach, however, OIT:

The objective of OIT is to increase your child’s tolerance to their allergen — in other words, to raise the threshold of food your child would need to consume to cause an allergic reaction. OIT can also reduce reaction severity, which is valuable in case of accidental exposures. OIT involves daily dosing of a prespecified quantity of the allergen, and consistently following the protocols is critical to achieving effectiveness. 

Children treated with OIT are still recommended to avoid the allergen in settings aside from the prespecified dose (unless the OIT dose is sufficient enough so that the allergen is no longer restricted). 

Furthermore, because OIT requires daily dosing, multiple caregivers may need to be educated on how to administer your child’s dose. Note that keeping epinephrine around is still recommended during OIT.

If you are interested in trying OIT, it is important to bring it up with your doctor and to find out what OIT options are available in your area. Not all allergists offer OIT, so it will be important to find out what resources you are able to access locally.

Xolair (omalizumab) is an injection approved by the FDA in February 2024 for food allergy treatment in children ages 1 or older. This makes it the newest approach to food allergy treatment. Xolair works by blocking the immunoglobulin E (IgE) antibodies that trigger an allergic reaction.

Like OIT, Xolair serves to build your child’s tolerance to the allergen by increasing the threshold for reactions and reduces reaction severity to accidental exposures. Unlike OIT, doses are given every 2-4 weeks rather than daily, making it potentially more manageable. 

Children treated with Xolair are still recommended to avoid allergen exposure. Unlike strict avoidance, however, the risks associated with accidental exposure or cross-contamination are mitigated. As with OIT, keeping epinephrine around is recommended. 

Existing food allergies are strongly linked to a higher risk of developing additional food allergies. In other words, if your child is allergic to walnut, they are more likely to also be allergic to other common allergens like shellfish or soy. One food allergy is already a headache; so trying to prevent that from turning into multiple allergies can be worth it!

Luckily, there are steps you can take to decrease the risk of additional allergies developing: keep introducing other allergens into your child’s diet. Early and consistent exposure to common allergens is recommended for all babies and is even more important for babies with a diagnosed food allergy. This might feel counterintuitive. Parents whose child has one food allergy may want to avoid other allergens in order to reduce the risk of a future reaction. Yet, premature avoidance of common allergens has actually been linked to increased risk of developing food allergies. Indeed, the critical window for allergy prevention continues from infancy to around age 5. This is because a child's immune system is changing the most rapidly during this time, so actions you take during this time have a higher likelihood of shaping its development.   

Hungry for more? Check out our how-to guide on how to safely introduce allergens. Some key takeaways include:

Skin prick tests are exactly what they sound like: a health professional pricks your child’s skin with a tiny amount of the allergen, usually on their back. Skin prick tests are designed to detect whether your child creates IgE antibodies to that food allergen — in other words, whether their immune system is sensitized to that food. If they are, a reaction looking like a small raised bump (similar to a mosquito bite) will appear, usually within 15 minutes. 

‍Skin prick tests will not tell you the severity of the allergy, nor if your child is allergic to a food they have never consumed. In other words, skin prick tests will only tell you if your child has IgE antibodies to the food. It’s possible for your child to have IgE antibodies to a specific food but not actually react to that food when consumed orally. This is why knowing whether your child has reacted to the food in the past is critical in interpreting results accurately.

Medications that suppress allergic reactions can interfere with skin tests. It’s often recommended to not take antihistamines, such as Children's Zyrtec, 3-5 days before the test. So the test may need to be postponed if the medication is taken too close before the test. 

Anaphylaxis can also cause skin tests to be falsely negative for 4-6 weeks after a reaction. So if the child has experienced anaphylaxis, talk to your doctor about possibly postponing the skin test. During this 4-6 week timeframe, blood tests may still be done. Check with your doctor on their specific recommendations.

If stopping antihistamines is not possible, your child cannot take a skin prick test for other reasons (such as severe eczema on the back), or the skin prick test results are unclear, your doctor may recommend a blood test.

Blood tests are also designed to detect whether your child has IgE antibodies to the food. Unlike skin prick tests, however, the results from a blood test can take days to weeks to return. This is because a blood test relies on a standard blood draw that is then sent to the lab to test for antibody levels. 

Similar to skin prick tests, blood tests can produce false positives which may suggest your child has a food allergy when they are not clinically allergic. And, like skin prick tests, blood tests do not necessarily tell you about the severity of the allergy, nor whether your child will react to foods they have not previously consumed.

Blood tests can also be used to monitor an allergy over time. Regular blood tests help you monitor whether your child’s allergy is persisting or resolving over time.

The oral food challenge is the most accurate way to diagnose food allergies. This is because the oral food challenge best recreates the real-world conditions of your child consuming the food. This allows your allergist to best understand how your child reacts and how severe the reaction is. Consuming the allergen in a clinical setting means medical professionals are on hand to respond to any concerning reactions.

To complete an oral food challenge, your child will consume increasing amounts of the suspected allergen over the course of one visit. Your child will start by consuming a very small amount of the allergen. If there is no reaction within 10-15 minutes, your child will consume more. This process will continue until the child shows an allergic reaction or reaches a full dose. 

Results from the oral food challenge are immediate, but only one potential allergen can be tested at a time. The oral food challenge is the most reliable test for food allergy diagnosis. The procedure can also be used if parents are nervous about introducing a new food at home, or to determine whether the child has outgrown the allergy.

If you are considering allergy testing, you probably already have a lot on your mind. Here are some tips for making the experience go as smoothly as possible:
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And, take care of yourself too! Testing can be stressful for both baby and parent. Just like the clinic might give your baby a treat for being a trooper through the process, be sure to treat yourself too.

Some companies produce and market allergy panels directly to consumers. Such tests usually require a blood sample taken at home. The sample is sent to their lab (which is not always accredited) where it is analyzed. Results are sent back identifying food allergies. 

Unfortunately, such kits can produce unreliable results that may lead to unnecessary dietary restrictions. There is a pretty wide range on the quality of these tests, with many not involving a licensed clinician and using controversial methodology to test for allergies. Discussion with your doctor remains the most recommended path to a food allergy diagnosis.

Allergic reactions can vary in how they look and their severity. The table below summarizes a range of potential symptoms as well as the corollary recommended action. Remember, knowledge is power. While we hope you will never need to take emergency measures, it is better to be prepared than to be caught unprepared!

Remember, the ultimate goal is that your child will be able to manage their allergy by themselves!