Peanut Allergy - in a Nutshell

Peanut allergy is often diagnosed in children less than 2 years old. In the past 1-2 decades, the number of children with peanut allergies has nearly doubled. Currently, 1 in 70 UK children suffer from peanut allergy; the vast majority (approximately 80%) will have this allergy for life.

While there are many types of food allergies, peanut allergies are particularly troublesome, for a number of reasons. Foremost is the fact that peanut allergy often results in more severe symptoms than other food allergies. Importantly, its symptoms can occur following exposure to only very tiny (or 'trace') amounts of peanut protein. Peanuts are a cheap source of dietary protein so they are used in a wide variety of food products, thus trace amounts of peanut protein can be found in many foods - from chocolate bars to fruit snacks.

Other than the complete avoidance of peanut, there is currently no available therapy for the treatment of peanut allergy. For these reasons, the UK Department of Health guidelines currently recommend that children (under the age of 3) from families with a strong history of allergic disorders may wish to avoid exposure to peanut and peanut-containing foods in order to reduce the potential of a serious allergic reaction.

What is a peanut allergy?

In a biological sense, peanut allergies are very similar to other allergies. They are caused by an over-reaction of the body's immune system to an otherwise harmless food protein. Substances that can trigger allergic reactions - "allergens" - are protein molecules, such as those from peanuts, house dust mite, grass pollen, cats and medicines.

In an allergic (or "sensitized") child, when the immune system detects peanut protein, antibodies known as IgE are produced. These antibodies then bind cells known as "mast cells," causing them to release chemicals like histamine, that cause inflammation in important tissues of the body, such as the lungs.

What happens during an allergic reaction to peanut?

The allergic reaction to peanut occurs soon after exposure (usually exposure through ingestion). Typical immediate allergic reactions include the development of hives (itchy bumps) on the face or body; blotching around the mouth (which may spread to the rest of the body); immediate runny nose, sneezing and itchy-watery eyes; coughing; choking or gagging; wheezing and trouble breathing; and cramps, vomiting and diarrhoea. The child’s behaviour may also change during an allergic reaction; for example, children may become uncharacteristically quiet or clingy. Although allergic reactions are usually mild to moderate in severity and usually terminate spontaneously or after the administration of an antihistamine, severe reactions - known as anaphylaxis – can occur. Anaphylaxis is a severe allergic reaction which involves several parts of the body and can be fatal if not treated immediately.

Dealing with peanut allergy

There is currently no cure for peanut allergy. Children who are allergic to peanuts must take great care to be vigilant in avoiding all traces of peanut from their diet. In addition, peanut allergic children often need to wear a Medic-Alert bracelet and, at all times, carry a pre-loaded adrenaline (epinephrine) injection kit with them (e.g. Epipen or Anapen) for use in event of a severe reaction. Patients should also carry an antihistamine for milder reactions and asthma medications if they have a diagnosis of both peanut allergy and asthma.

Learn more about the dangers of anaphylaxis...

[top]