Allergies

Allergies are an immune system response to substances that are harmless to most other people. The immune system normally protects the body from harmful things, such as bacteria or viruses. Sometimes, the immune system will mistakenly respond and try to defend itself against things such as pollen, dust, or certain foods or medicines. Substances that cause allergies are called allergens.

If you notice your child sneezes or coughs a lot, or often develops a rash or hives, then he or she may have allergies.

Allergies are caused by responses by the immune system to substances that are harmless to most other people. The immune system normally protects the body from harmful things, such as bacteria and viruses. It does this by producing large amounts of antibodies, called immunoglobulin (ih-myoo-noh-GLOB-yuh-lin). This chemical helps fight harmful things. Sometimes, the immune system will mistakenly respond and try to defend itself against things that may not be harmful, such as pollen or dust. The substances that cause these responses by the immune system are known as allergens.

Why the immune system targets certain substances is unknown. These reactions may begin to develop shortly after birth. In many cases, they may not develop until your child is older. Children will often experience allergies from food, pets, insects, trees, and plants. The body’s reaction to these allergens may be mild or serious. In some cases, they may be life-threatening.

An allergic reaction can happen anywhere on your child’s body including the skin, nose, eyes, throat, stomach, and lungs. In some cases, the symptoms may appear as if your child has a cold.

Common symptoms of an allergic reaction include:

• Sneezing
• Runny or stuffy nose
• Scratchy throat
• Red, itchy, watery eyes
• Red, itchy skin
• Hives (swollen, red bumps on the skin)
• Shortness of breath
• Wheezing
• Difficulty breathin

More serious symptoms, such as difficulty breathing or loss of consciousness, may be signs of anaphylaxis (an-uh-fuh-LAK-sis). Anaphylaxis is a severe allergic reaction that needs immediate treatment. 

You should contact your child’s healthcare provider if he or she has symptoms of allergies. Your child may be referred to a specialist called an allergist. An allergist is a physician who diagnoses and treats allergies.

Allergies are often passed down from parents to children, but not always. Some children have allergies when their parents don’t. And when a child does inherit allergies, they may not be allergic to the same thing as the parent. They’re just more likely to have allergies. A child who is allergic to one thing is more likely to be allergic to other things.

Many things can trigger allergic reactions in children. The most common triggers (or allergens) include the following:

• Tree, grass, and weed pollens
• Molds
• Dust Mites
• Animal dander
• Medicines
• Latex
• Insects, especially cockroaches and bees

Foods that commonly cause allergies include:

• Cow’s milk
• Eggs
• Fish and shellfish
• Peanuts and other tree nuts
• Soy
• Wheat

Your child’s healthcare provider may order tests to find out if your child has an allergy. These tests include:

Skin test. The skin test measures the immune system’s response to certain allergens. During an office visit, the healthcare provider will place diluted solutions of certain allergens on or under your child’s skin. If a small red area appears on the skin, then your child likely has an allergy to that substance.

Blood test. A blood test will help measure your child’s immune response to certain allergens. The test can detect the level of immunoglobulin in your child’s bloodstream when exposed to certain substances. Blood tests may be less sensitive than skin tests in detecting allergies.

Food challenge test. Under the careful supervision of an allergist, your child will be given specific doses of foods to assess reactions.

There’s no cure for allergies, but your child’s symptoms can be managed. A first step in managing allergies is to teach your child what they are allergic to and how to avoid the substance whenever possible. Teach them what to do if they come in contact with it.

Other treatments will depend on the type of allergies your child is experiencing.

Some allergy problems may not need any treatment. However, sometimes allergies can interfere with your child’s day-to-day activities. In these cases, your child’s healthcare provider may recommend the following treatment options:

• Antihistamines
• Eye drops
• Nasal sprays
• Medicine to manage asthma symptoms caused by allergies

A long-term treatment option for your child is having allergy shots (also called immunotherapy). Allergy shots, reduces your child’s sensitivity to substances that cause allergies.

The best way to prevent allergies is to avoid the substances that cause allergic reactions. Teach caregivers and family members what your child is allergic to and ask them to help your child. If your child has food allergies, be sure to read labels to see if a packaged food contains your child’s allergens.

Intermountain fact sheet: Preventing Food Allergies in Children

American Academy of Allergy, Asthma, and Immunology