Food allergy basics

How allergies work - video

Have you ever wondered what happens inside your body for you to develop allergies?

This short animation provides a simple explanation about how we develop allergies and also what happens in our body to cause symptoms of an allergic reaction.

What is a food allergy?

Food allergy is an immune system reaction, usually to the protein in food.
A food allergen is food or protein that causes an allergic reaction.
When the food allergen is eaten by someone who is allergic to it, their immune system releases large amounts of chemicals that trigger symptoms. The symptoms can affect their lungs, heart, skin and gut.
Allergic reactions to food can be mild to moderate, or severe.
Severe, life-threatening allergic reactions are called anaphylaxis.

How common is food allergy?

In Australia, about 1 in 10 babies, 1 in 20 children and 1 in 50 adults have food allergy.

Which foods cause allergic reactions?

The common allergy causing foods are peanut, tree nuts, egg, milk (dairy), sesame, fish, crustacea, mollusc, soy, wheat and lupin.

However, any food has the potential to cause an allergic reaction.

There is no cure for a food allergy. To prevent having a reaction, people with food allergy must avoid the food or foods they are allergic to. Reactions can happen to very small amounts of a food, for example, a crumb or drop.

Is a food intolerance the same as a food allergy?

No. A food intolerance and a food allergy are different.

A food intolerance does not involve the immune system. A food intolerance usually happens because the person can’t digest a food properly. It can make people feel sick, but is not life-threatening.

Signs and symptoms of an allergic reaction to foods

Allergic reactions to food can be mild to moderate, or severe. Anaphylaxis is the most severe type of an allergic reaction and is life-threatening.

MILD to MODERATE allergic reaction

Swelling of lips, face, eyes
Hives or welts
Tingling mouth
Abdominal pain, vomiting

SEVERE allergic reaction (anaphylaxis)

Watch for ANY ONE of the following:

Difficult or noisy breathing
Swelling of tongue
Swelling/tightness in throat
Difficulty talking and/or hoarse voice
Wheeze or persistent cough
Persistent dizziness or collapse
Pale and floppy (young children)

Anaphylaxis usually happens within minutes after eating the food but can also take up to 2 hours.

You may not have mild to moderate signs before anaphylaxis.

This video explains the signs and symptoms of an allergic reaction and what to do if someone has an allergic reaction.

Treating anaphylaxis

Anaphylaxis needs quick treatment with adrenaline (epinephrine) which is injected into the outer mid-thigh muscle.

The Australasian Society of Clinical Immunology and Allergy (ASCIA) Action Plans provide information about when and how to give adrenaline.

Adrenaline injectors contain a single dose of adrenaline and are easy to use.

There are two types of adrenaline injectors in Australia. They are called EpiPen® and Anapen®.

There is a different ASCIA Action Plan for each device because they are administered differently. ASCIA Action Plans have instructions on how to manage an allergic reaction.

Always keep your ASCIA Action Plan with your adrenaline injector device.