Food allergy is an immune system overreaction that occurs soon after eating a certain food or repetitive eating of a trigger food. Even a tiny amount of the allergy-causing food can trigger signs and symptoms such as digestive problems, hives or swollen airways. In some people, a food allergy can cause severe symptoms or even a life-threatening reaction known as anaphylaxis.
Food allergy is more common in infants and children. While there’s no cure, some children outgrow their food allergy as they get older. It’s easy to confuse a food allergy with a much more common reaction known as food intolerance. While bothersome, food intolerance is a less serious condition that does not involve the immune system.
Signs and symptoms of food allergy may include:
- Rash – Urticaria (Hives) are the most common allergic skin reaction to a food. They are red, raised, itchy areas of the skin which appear in clusters on the skin and usually do not stay in one place on the skin for more than 24 hours. Eczema, which is a more chronic skin problem characterized by itchy, red, scaly skin can also occur.
- Mouth/Throat symptoms – itching, tingling, or swelling of the lips, tongue, throat, or mouth
- Gastrointestinal symptoms – nausea/vomiting, diarrhea, or abdominal cramping
- Chest symptoms – shortness of breath, repetitive coughing, or wheezing
- Heart – weak pulse, low blood pressure, fainting, paleness
The most common food allergens include:
- Milk, egg, wheat, peanut, tree nuts, and soy make up 90% of all food allergies in children.
- In adults, fish and shellfish are high on the list of food allergens as well.
- We’ve been hearing more and more about peanut and other nut allergies which tend to produce some of the most serious, life threatening reactions. Whereas milk and egg allergies in children are most likely to be outgrown by age 5, only about 20% of nut allergies are outgrown.
How are food allergies diagnosed? – It’s an art not a science !
- Blood tests can be helpful in making the diagnosis. Food specific IgE antibody testing can determine what the likelihood is of a future reaction to that particular food.
- Keeping a 2 week food diary is very helpful in identifying food triggers, especially with repetitively eaten foods.
- Food elimination and then challenges can be done based on the review of the blood tests and food diary.
What is the treatment?
- Avoidance of known food allergens is the best way to prevent reactions from occurring. It is important to read labels and ask restaurants for a complete list of ingredients before ingesting foods.
- All people with severe acute food allergies should carry an epipen with them at all times. An epipen is an adrenaline self-injectable that can be used in case of accidental ingestion of a known allergen.
- All people with severe acute food allergies should also wear an ID bracelet stating all their food allergies clearly.
- For children with food allergies, school personnel including the teachers, administrators, and school nurses should be aware of the allergy and know how to use an epipen correctly