Peanut allergy in children

What is a peanut allergy? 

Peanut allergy affects around 2% of (or 1 in 50) children in the UK. Instances of peanut allergies have increased in recent years, resulting in a range of allergic reactions from mild symptoms to life-threatening anaphylaxis. 

For people with peanut allergies, allergic reactions can be at best uncomfortable and at worst life-threatening. Peanut allergy is one of the most common food allergies, with close to 300,000 individuals in the UK experiencing allergic symptoms as a response to consuming peanuts.  

A peanut allergy occurs when the body mistakenly identifies peanut proteins as harmful, causing specific antibodies to be released. When your child consumes peanuts or, in some cases, comes into contact with them (for example via the skin or inhalation), their immune system triggers the release of chemicals like histamine which then leads to allergic symptoms.

What causes a peanut allergy? 

Genetic factors play a big part in a peanut allergy. If one or both parents have allergies, hay fever, asthma or eczema, the risk of their child having a peanut allergy is higher. Specific genes may also make a child more likely to have food allergies, including peanut allergies. 

Additionally, if your child has eczema, especially early onset eczema, they may also be more likely to develop a peanut allergy. 

Some research suggests that introducing peanut into a child’s diet in infancy prevents them from developing a peanut allergy into adolescence. The research found that feeding children peanuts (as nut butter or ground peanuts mixed with foods) regularly from infancy to the age of 5 reduced the rate of peanut allergy by 71%, even if the children subsequently avoided peanuts after their early childhood years.  

Therefore, it’s reasonable to assume that children who do not consume peanuts in infancy may be more likely to develop a peanut allergy. 

What are the symptoms of a peanut allergy? 

The symptoms of peanut allergies can vary from person to person. Reactions to peanuts can also be different each time for the same person, depending on how much peanut they have consumed on a given occasion. 

Examples of mild allergic reactions to peanuts are: 

• itching in the mouth  
• runny nose  
• skin reactions such as rashes or hives  
• stomach cramps or vomiting
  

A life-threatening reaction to peanuts (or any food you’re allergic to) is called anaphylaxis, which requires emergency medical treatment. Symptoms of anaphylaxis can include:  

• difficulty breathing  
• difficulty swallowing 
• hoarse voice 
• loss of consciousness 
• persistent cough or wheeze 
• persistently dizzy, pale, or floppy  
• swelling inside the throat or tongue
  

People with severe peanut allergies should always carry an adrenaline auto-injector with them to treat the most dangerous anaphylaxis symptoms.  

You should always call 999 in the case of anaphylaxis, even if you have used an autoinjector already.  

Diagnosing a peanut allergy 

Diagnosing a peanut allergy can be difficult as symptoms can vary depending on the person. However, there are some methods to determine if your child has a peanut allergy and some tests can also help determine how severe their allergy is. 

Skin prick test 

A skin prick test is a straightforward method of allergy testing. A very small amount of peanut protein is placed on your child’s skin, either on the inside of their forearm or on their leg. Our allergy specialist will scratch the skin with a sterile lancet which allows the peanut protein to enter the top layer of their skin. If a red bump develops in the first 20 minutes, it can indicate an allergy to peanut. 

Blood test 

Our children’s allergy service offers patients a blood test to measure the levels of peanut-specific immunoglobulin E (IgE) antibodies in their blood. Higher levels of IgE suggest a possible peanut allergy. This blood test can help our allergy specialists to assess the likelihood of your child having an allergic reaction to peanuts, as it provides a measurable level of the antibodies. In many cases, it is used alongside a skin prick test to provide an initial diagnosis. 

Component resolved diagnostics (CRD) 

This is an advanced type of blood test that identifies specific peanut proteins that are known to trigger the allergy. CRD helps our specialists to differentiate between mild sensitivities to peanut proteins and more severe allergic reactions, which allows them to recommend appropriate treatment for your child. 

CRD is recommended for children who have received mixed results from previous allergy tests, as well as for children with multiple food or pollen allergies, who may be affected by cross-reactivity. 

Oral food challenge 

If it’s not clear whether your child is allergic to peanuts specifically (if it is not clear if they are allergic to peanut based on the allergy tests), our specialists may recommend an oral food challenge. This is carried out in a medical setting with supervision from our specialist allergy team. It involves your child eating increasing amounts of peanut while we monitor them for a reaction. The test is very accurate but, due to the risk of severe reactions, it must be carried out under medical supervision.

Treatment for peanut allergy 

Palforzia peanut immunotherapy 

Our allergy specialists at Evelina London Children’s Hospital are proud to offer an innovative treatment for children with severe peanut allergies in the form of Palforzia. 

Palforzia is a peanut immunotherapy drug designed to minimise the severity of children’s allergic reactions to peanuts. Our world-leading allergy specialists at Evelina London took part in the clinical trials for Palforzia, which is now available to treat children aged 4-17 with a confirmed peanut allergy. 

Palforzia is the first licensed treatment for peanut desensitisation in children. It was developed to contain the specific components responsible for triggering allergic reactions and stands as the only immunotherapy for a food allergy approved by NICE. 

Palforzia functions by slowly increasing the body’s tolerance to peanuts through a technique known as oral immunotherapy (OIT). This approach involves gradually exposing children with food allergies to small quantities of peanut over time. The process supports the body in developing a tolerance and lowers the likelihood of an allergic reaction caused by accidental exposure. 

Learn more about Palforzia and how our specialists will determine if it’s a suitable treatment option for your child. 

Adrenaline auto-injectors  

Adrenaline auto-injectors (known as Epipen or Jext pens) are the first-line treatment for anaphylaxis and are essential for children with peanut allergies to have on their person, in case of accidental peanut consumption. 

Adrenaline is a hormone that counteracts the effects of severe allergic reactions, such as those caused by peanuts. Adrenaline auto-injectors work by delivering a rapid dose of this hormone to minimise the effects of an allergic reaction to peanuts, and are a highly effective, life-saving emergency treatment. 

Speak to our team about acquiring EpiPens if you know your child has a peanut allergy, or about testing if you wish to receive a diagnosis for a peanut allergy, in order to develop a treatment plan for your child.