Children's Hospital Colorado

Food Allergies in Kids

What is a food allergy?

A food allergy is an adverse immune system response to a food protein that can result in symptoms related to a number of different parts of the body including the gastrointestinal tract. Symptoms most often include hives but can also include facial swelling, tingling or burning in the mouth, vomiting and diarrhea.

Food allergy symptoms can be immediate, typically occurring within minutes to an hour after exposure, or delayed, occurring several hours later. Other diseases, such as lactose intolerance, are caused by eating certain foods, but these are not food allergies.

What causes food allergies?

It is not exactly known what causes food allergies. Typically our body's immune system is able to tolerate eating most foods that we come in contact with and digest every day. During a food allergic response, the body develops an inappropriate immune response to the ingested food resulting in allergic symptoms.

Who gets a food allergy?

Anyone can develop a food allergy but a child is more likely to develop food allergies when other family members have a history of an allergic disease such as asthma, eczema, hay fever or food allergies. The majority of childhood food allergies develop in the first 1 to 2 years of life although new food allergies can develop throughout childhood. Some children will outgrow their allergies while others will remain allergic into adolescence and adulthood.

What are the signs and symptoms of food allergies?

Allergic reactions can happen immediately (from seconds to one hour) after eating a food, or be delayed (hours or days after exposure). Immediate symptoms can include:

  • Hives
  • Itching of mouth, lips, tongue, throat, eyes, skin or other areas
  • Nausea and/or vomiting
  • Swelling of lips, tongue, eyelids or the whole face
  • Difficulty swallowing
  • Wheezing and/or shortness of breath

The most serious symptom is anaphylaxis, a whole body response to an allergen that can result in shock and cause impaired breathing and blood flow (circulation). Anaphylaxis is a serious and life threatening allergic response that requires immediate medical attention. Call 911 if your child cannot breathe.

Delayed symptoms can include:

  • Abdominal pain and/or stomach cramps
  • Poor appetite
  • Diarrhea
  • Eczema or rash

What tests are used to diagnose food allergies?

The most common tests for allergies are skin prick testing and blood tests (ImmunoCAP).

Skin prick testing is typically performed in an office setting; testing involves pricking the skin with a small amount of the suspected allergen in a liquid on the arm or back. Sometimes this will cause a raised area to develop, like a small bug bite or hive, at the site of the prick. Negative testing does not rule out an allergy and a positive test does not mean your child will have a reaction if that food if ingested. Your allergist will determine whether or not the test is abnormal or not.

How do doctors at Children's Hospital Colorado make a diagnosis?

Our allergists perform allergy tests and, importantly, interpret their results. An allergist will decide on the most appropriate allergy testing for your child based on his or her history or allergic reactions. Based on your child's symptoms it may also be recommended that other testing be performed, such as a supervised food challenge, an endoscopy or colonoscopy by a pediatric gastroenterologist here at Children's Colorado.

How is a food allergy treated?

Food allergies are treated most commonly either by completely avoiding the allergen or, in some cases, immunotherapy (or desensitization). Immunotherapy is recommended and performed by allergists. Immunotherapy is not a cure, but can readjust the immune system response enough to allow children and adults to safely consume foods to which they were previously allergic.

Anaphylaxis, the most extreme allergic reaction, is an emergency and needs to be treated as such. Anyone with food allergies should have epinephrine (e.g., EpiPen) prescribed to them and carry this pen with them to be used in the case of anaphylaxis.

Some children with multiple food allergies also have eosinophilic esophagitis or other disorders. The Gastrointestinal Eosinophilic Diseases Program (GEDP) is a multidisciplinary program that cares for children with eosinophilic inflammation of their intestines, otherwise called, eosinophilic gastrointestinal diseases (EGIDs) that include eosinophilic esophagitis, eosinophilic gastritis, eosinophilic gastroenteritis and eosinophilic colitis. Many children with EGIDs have food allergies and could benefit from the GEDP.

Why choose Children's Colorado for your child's food allergies?

Allergy specialists at Children's Colorado are leaders in allergy research and treatments. In conjunction with the University of Colorado School of Medicine our allergy specialists at the Children's Colorado are on the forefront of evaluating new methods of allergy testing and new medications for allergy treatment.

In our clinics, extensive diagnostic testing is available for both infants and older children. We believe a multidisciplinary approach to allergy management is the best way to improve quality of life for our young patients. Here at Children's Colorado, your allergist will work with an experienced team including doctors, nurses, dietitians, social workers, child life specialists and therapists. Allergists also work closely with other specialists, including gastroenterologists, to provide appropriate diagnostic evaluation and to best manage your child's allergies.

  • The Food Allergy and Anaphylaxis Network offers information about living with food allergies, current research and support networks.
  • GastroKids focuses on helping parents and kids manage gastrointestinal disorders including food allergies.