Milk, eggs, soy, wheat, tree nuts, peanuts, fish, and shellfish are among the most common foods that cause allergies.
Food allergies can cause serious and even deadly reactions. So it's important to know how to recognize an allergic reaction and to be prepared if one happens.
With a food allergy, the body reacts as though that particular food product is harmful. As a result, the body's immune system (which fights infection and disease) creates antibodies to fight the food allergen .
Every time the person eats (or, in some cases, handles or breathes in) the food, the body releases chemicals like histamine . This triggers allergic symptoms that can affect the respiratory system, gastrointestinal tract, skin, or cardiovascular system.
Symptoms can include:
People often confuse food allergies with food intolerance because of similar symptoms. The symptoms of food intolerance can include burping, indigestion, gas, loose stools, headaches, nervousness, or a feeling of being "flushed." But food intolerance:
A child could be allergic to any food, but these eight common allergens account for 90% of all reactions in kids:
In general, most kids with food allergies outgrow them. Of those who are allergic to milk, about 80% will eventually outgrow the allergy. About two-thirds with allergies to eggs and about 80% with a wheat or soy allergy will outgrow those by the time they're 5 years old. Other food allergies may be harder to outgrow.
Food allergy reactions can vary from person to person. Sometimes the same person can react differently at different times. So it's very important to quickly identify and treat food allergy reactions.
Reactions can:
Food allergy reactions can affect any of these four areas of the body:
Sometimes, an allergy can cause a severe reaction called anaphylaxis, even if a previous reaction was mild. Anaphylaxis might start with some of the same symptoms as a less severe reaction, but can quickly get worse. The person may have trouble breathing or pass out. More than one part of the body might be involved. If it isn't treated, anaphylaxis can be life-threatening.
If your child might have a food allergy, the doctor will ask about:
The doctor will look for any other conditions that could cause the symptoms. For example, if your child seems to have diarrhea after drinking milk, the doctor may check to see if lactose intolerance could be the cause. Celiac disease — a condition in which a person cannot tolerate the protein gluten — also can cause similar symptoms.
The doctor might refer you to an allergist (allergy specialist doctor), who will ask more questions and do a physical exam. The allergist probably will order tests to help make a diagnosis, such as:
If the test results are unclear, the allergist may do a food challenge:
More often, though, food challenge tests are done to see if people have outgrown an allergy.
If your child has a food allergy, the allergist will help you create a treatment plan. Treatment usually means avoiding the allergen and all the foods that contain it.
You'll need to read food labels so you can avoid the allergen. Makers of foods sold in the United States must state whether foods contain any of the top eight most common allergens: milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, or soy.
For more information on foods to avoid, check sites such as the Food Allergy Research and Education network (FARE).
There's no cure for food allergies. But medicines can treat both minor and severe symptoms. Antihistamines might be used to treat symptoms such as hives, runny nose, or belly pain from an allergic reaction.
If your child has any kind of serious food allergy, the doctor will want him or her to carry an epinephrine auto-injector in case of an emergency.
An epinephrine auto-injector is a prescription medicine that comes in a small, easy-to-carry container. It's easy to use. Your doctor will show you how. Kids who are old enough can be taught how to give themselves the injection. If they carry the epinephrine, it should be nearby, not left in a locker or in the nurse's office.
Wherever your child is, caregivers should always know where the epinephrine is, have easy access to it, and know how to give the shot. Staff at your child's school should know about the allergy and have an action plan in place. Your child's medicines should be accessible at all times. Also consider having your child wear a medical alert bracelet.
Signs and symptoms of anaphylaxis that would require epinephrine include:
Every second counts in an allergic reaction. If your child starts having serious allergic symptoms, give the epinephrine auto-injector right away. Also give it right away if the symptoms involve two different parts of the body, like hives with vomiting. Then call 911 and take your child to the emergency room. Your child needs to be under medical supervision because even if the worst seems to have passed, a second wave of serious symptoms can happen.
It's also a good idea to carry an over-the-counter (OTC) antihistamine for your child, as this can help treat mild allergy symptoms. Use antihistamines after — not as a replacement for — the epinephrine shot during life-threatening reactions.
Reviewed by: Stephen F. Dinetz, MD
Date Reviewed: 10-08-2018