Allergy testing for babies and children

Signs of food allergies 

Food allergies can cause symptoms that can range from mild to life-threatening. Specific symptoms can cause: 

• Skin problems, such as hives, itchy rashes or swelling 
• Digestive issues, such as upset stomach, nausea, vomiting or diarrhea 
• Respiratory problems, such as trouble breathing, wheezing, sneezing or throat tightness 
• Circulatory issues, such as lightheadedness, pale skin or loss of consciousness 

If your child has signs of a food allergy, see their health care provider. They may refer you to an allergist. 

Food allergy testing 

Kids’ allergy testing is similar to allergy testing in adults. Your child’s allergist will ask you about your child’s health history and symptoms. They’ll likely want to know the following: 

• The food you believe your child may be allergic to 
• How much of the food they ate before they had a reaction 
• The specific symptoms they experienced 
• How long it took after eating the food for symptoms to start
• How long symptoms lasted  

Your child’s allergist will decide if your child needs allergy testing and which tests to perform. 

Skin allergy tests 

For a skin allergy test, your child will have a small amount of liquid food extract placed onto the skin of their back or forearm. They’ll receive one drop for each food they’re being tested for. Next, a provider will gently prick the locations of their skin that contain the liquid with a needle. This lets a small amount of food get beneath their skin. If a small, red and raised bump appears 15-20 minutes later, it probably means your child is allergic to that food. 

Allergy blood tests 

In allergies, the immune system overreacts to an allergen and produces immunoglobulin E (IgE) antibodies. Food allergy blood tests measure the amount of IgE antibodies in your child’s blood to certain foods. For this test, a health care provider will take a small sample of blood from a vein in your child’s arm. If the blood test is positive for IgE antibodies to a specific food, your child is likely allergic to that food. 

Oral food challenge tests 

Positive results on skin tests or blood tests often mean your child has a food allergy, but results aren’t always conclusive. In these cases, your child’s allergist may recommend an oral food challenge test. Oral food challenges may also be done to figure out if a child has outgrown a food allergy. The challenge involves eating or drinking a small amount of the food in increasing amounts over time to see if your child has a reaction. The challenge is done in a doctor’s office or hospital under a health care provider’s care. This way, your child can receive immediate treatment if they have an allergic reaction. 

Elimination diet 

Your child’s allergist may suggest trying an elimination diet if they have mild symptoms. This involves removing all suspect foods from their diet, reintroducing them one at a time and noting their symptoms. If they react to a specific food, your child may be allergic to that food. If your child is breastfed, you may need to do an elimination diet and note your child’s symptoms when you remove foods from your diet and reintroduce them. 

Know that food allergies can only be diagnosed by a qualified health care provider. There are several at-home allergy tests available that measure IgG antibodies to foods (not IgE), but the American College of Allergy, Asthma and Immunology says they aren’t useful or effective. 

Is there a gluten allergy test? 

Gluten is a protein naturally found in wheat, barley and rye. “Gluten allergy” is an incorrect term. It’s often misused to describe gluten-related conditions such as an allergy to wheat, a sensitivity to gluten or celiac disease (an autoimmune disorder where the intestinal lining can’t absorb and is harmed by foods that contain gluten). Testing for wheat allergies is the same as testing for other food allergies. To tell if your child has a gluten sensitivity, their provider may suggest trying an elimination diet. For celiac disease testing, your child may need a blood test and a biopsy of their small intestine. 

Non-food related allergy testing 

Note that children can be allergic to other things besides food. Testing for other allergens, such as pollen and mold, may be done through blood or skin tests, or, through a patch test. A patch test will tell if a substance, such as latex, fragrances or medications, is causing contact dermatitis, or allergic skin irritation. For this test, a suspected allergen is placed onto a patch, and then the patch is placed onto your child’s skin. They’ll wear the patch for about 48 hours and then their provider removes it. Irritation at the site of the patch can indicate an allergy. 

Allergy testing cost 

Blood tests tend to cost more than other allergy tests. In general, skin tests combined with a physical exam and information about your child’s symptoms is the most cost-effective way to diagnose food allergies. To learn how much allergy testing costs, contact your health insurance provider and allergist. 

If your child is diagnosed with an allergy, take heart in knowing that your child’s symptoms can be managed. Work with your child’s allergist to learn how to avoid their allergens and what to do if your child has an allergic reaction.