Your child gets a rash after eating eggs. Or maybe they're itchy and unsettled after a meal with dairy. Is it an allergy, or something else?
Allergies in children can be confusing to navigate. Here's an overview of symptoms, testing, and what you can do — based on current AAP and FARE guidelines.
How Common Are Allergies in Children?
According to the American Academy of Allergy, Asthma and Immunology (AAAAI), approximately 1 in 13 children in the US has a food allergy. The most common allergic conditions are:
- Atopic eczema (atopic dermatitis) — affects up to 15–20% of children
- Food allergy — affects 8% of children; many outgrow it
- Hay fever (allergic rhinitis) — typically develops from ages 3–5
- Asthma — affects approximately 10% of children
Allergies have a hereditary component. If one or both parents have allergies, the risk is higher for the child.
Food Allergy vs. Food Intolerance — What's the Difference?
Many people confuse allergy and intolerance, but they are two different things.
Food allergy involves the immune system. The body reacts to a protein in the food as if it were dangerous. Reactions can come quickly (minutes to hours) and can in rare cases be severe.
Food intolerance does not involve the immune system. It means the body has difficulty digesting certain substances, such as lactose. Symptoms are unpleasant but not dangerous.
According to FARE, cow's milk protein allergy is the most common food allergy in infants. It affects approximately 2–3% of babies and usually resolves by age 3–5.
Allergy Symptoms in Children
Skin Reactions
- Rash, hives (urticaria), or swelling
- Atopic eczema that worsens after certain foods
- Itching around the mouth or on the body
- Redness in the face
Digestive Symptoms
- Vomiting or nausea after a meal
- Stomach pain and colic-like distress
- Diarrhea or loose stools
- Blood or mucus in stools (can occur with cow's milk protein allergy)
Respiratory Symptoms
- Runny or stuffy nose
- Sneezing
- Coughing or wheezing
- Swelling of the throat (serious — call 911)
Severe Reactions (Anaphylaxis)
In rare cases, an allergy can cause a life-threatening reaction. Symptoms include difficulty breathing, significant swelling, pallor, and loss of consciousness.
Call 911 immediately if your child has difficulty breathing, swelling of the face or throat, or appears limp and pale after contact with a possible allergen. Anaphylaxis requires emergency treatment.
The Most Common Allergens in Children
According to FARE and the AAP, these foods are responsible for most allergic reactions in children (the "Big 9" in the US):
- Cow's milk — most common in infants
- Eggs — second most common; many tolerate cooked egg even if they react to raw
- Peanuts — can cause serious reactions
- Tree nuts — almonds, cashews, walnuts
- Fish — more common in older children
- Shellfish — most common food allergy in adults
- Wheat — can be difficult to distinguish from celiac disease
- Soy — less common than in some other countries
- Sesame — newly added to the US list of major allergens in 2023
How Is Allergy Tested in Children?
At the Pediatrician or Allergist
The doctor starts with a detailed medical history. When did your child react? What did they eat? How quickly did the reaction come? This information is extremely useful.
Blood Test (Specific IgE)
A blood test can measure the level of allergy antibodies (IgE) against specific foods. A positive test means your child is sensitized, but does not necessarily mean they have a clinical allergy.
Skin Prick Test
Small amounts of allergen are placed on the skin with a light prick. A reaction (swelling and redness) within 15–20 minutes suggests sensitization.
Elimination Diet and Oral Food Challenge
The gold standard for food allergy is to remove the suspected food from the diet for 2–4 weeks, then gradually reintroduce it under medical supervision. This should always be done with a doctor or allergist.
Keep a food and symptom diary for your child. Log meals, any reactions, timing, and severity. This gives your doctor valuable documentation and makes it much easier to identify patterns.
Early Food Introduction and Allergy Prevention
Guidelines have changed in recent years. Research shows that early introduction of allergenic foods can actually protect against allergy.
Current AAP recommendations:
- Start solid foods at around 6 months — include allergenic foods early
- Don't delay allergenic foods — offering eggs, fish, and nut butters from the start of solids does not increase risk
- Breastfeeding provides protection — exclusive breastfeeding to 6 months offers a good foundation
- Introduce one new food at a time — wait 1–2 days between new allergens to be able to identify any reactions
Read more about safe allergen introduction in our guide to introducing allergens to your baby.
Treatment and Management of Allergies
Avoidance
The main treatment for food allergy is avoiding the food that causes the reaction. Your doctor or a registered dietitian can help you ensure your child gets all the nutrients they need.
Medications
- Antihistamines — reduce mild to moderate reactions
- Epinephrine auto-injector (EpiPen) — prescribed for children at risk of anaphylaxis
- Topical corticosteroids — for atopic eczema
Follow-Up
Most children with milk and egg allergy outgrow it. Your doctor will recommend regular check-ups and possibly an oral food challenge to see whether your child has developed tolerance.
Allergy at Daycare or School
When your child has an allergy, the daycare or school needs to be informed and have an action plan. FARE recommends:
- Written documentation from your doctor listing allergens and instructions
- Training of staff in using an epinephrine auto-injector if prescribed
- Adapted diet at daycare or school
- A visible emergency action plan posted in the kitchen area
Frequently Asked Questions
Can my child outgrow their allergy?
Yes, many children outgrow food allergies. Most children outgrow cow's milk and egg allergy by school age. Peanut, tree nut, fish, and shellfish allergies tend to be more persistent.
Should I avoid giving my baby allergenic foods to be safe?
No. The AAP recommends introducing allergenic foods from around 6 months. Delaying introduction does not protect against allergy and may actually increase the risk.
Should my child have an allergy test even if they haven't had a reaction?
Routine allergy testing of children with no symptoms is not recommended. Testing should be done when there is a specific reason to suspect an allergy, based on symptoms after exposure.
Track Your Child's Health
If you suspect an allergy, it's a good idea to document what you observe. A symptom and food diary — logging meals, reactions, and timing — gives your doctor useful information when you come in.
You can also read our guide to introducing allergens to your baby for more information.