Tree nut allergy factsheet

Introduction

Tree nut allergies are one of the most common and severe allergies in children. 

Common tree nuts include:

  • almonds
  • brazil nuts
  • cashews
  • chestnuts
  • hazelnuts
  • hickory nuts
  • macadamia nuts
  • pecans
  • pistachios
  • walnuts.

Children allergic to one tree nut are often allergic to other tree nuts. Cashew is the most common tree nut allergy. 

Tree nuts are different from peanuts. Peanuts come from a plant family called legumes that grow in the ground. 

Around 1 in 3 children with tree nut allergies are allergic to peanuts.

Some children are more at risk of having a tree nut allergy. Risk factors include:

Like any other allergy, it is important to talk to your child’s doctor before reintroducing foods that have previously caused an allergic reaction.

 Signs and symptoms

Allergic reactions can be fast and happen within minutes of exposure to tree nuts but can take up to 2 hours to develop.

Reactions can include:

  • hives or welts
  • redness of the skin
  • vomiting and stomach ache
  • tingling and swelling of the mouth, lips, face, and eyes.

If your child is showing signs of an allergic reaction for the first time, if symptoms do not get better, or if you are worried, see your local doctor as soon as possible. 

Anaphylaxis

Some children can have a more severe allergic reaction called anaphylaxis.

Signs of anaphylaxis include: 

  • wheezing, difficult, or noisy breathing 
  • swelling of the tongue
  • swelling or tightness in the throat
  • a persistent cough
  • difficulty talking or a hoarse voice
  • dizziness
  • becoming pale and floppy in young children
  • collapsing.

If your child has signs of anaphylaxis, you should:

  • follow your child’s ASCIA action plan for anaphylaxis if you have one
  • use an EpiPen or Anapen if there is one available
  • call Triple Zero (000) for an ambulance.

Diagnosis

If you think your child has had an allergic reaction that is not anaphylaxis, write down the following and see your local doctor as soon as possible:

  • time your child was exposed to the tree nut
  • time of reaction
  • type of reaction
  • amount of tree nut eaten.

A specialist doctor can diagnose a tree nut allergy based on your child's:

  • medical history
  • signs and symptoms
  • results from allergy tests.

Some children will grow out of their tree nut allergy. 

A food challenge can be done to figure out whether your child has grown out of their allergy and whether tree nuts can be reintroduced to their diet safely. Food challenges are done under the supervision of a doctor in the hospital. 

Treatment

Your child's doctor will find the best possible treatment for their allergy based on their individual health needs. In most cases, your child must carefully avoid tree nuts in their diet. 

Your child’s doctor will develop an ASCIA Action plan to share with anyone who cares for your child, including parents, carers, childcare and schools. 

ASCIA Action plans are used to manage allergies and allergic reactions safely.

Children at risk of anaphylaxis will also need an adrenaline autoinjector, also known as an EpiPen® or Anapen®.

 Management

Common sources of tree nuts

Tree nuts are a common ingredient in food, so they can be difficult to avoid. 

Some foods will visibly contain tree nuts, for example, when nuts are used as a garnish. 

They can also be in other foods like:

  • baked goods - for example, cake, muffins, and biscuits
  • desserts - for example, carrot cake, chocolate, ice cream, and nougat
  • breakfast cereals, muesli, and granola
  • dips, sauces, spreads, and marinades - for example, tikka masala, romesco sauce and nut butter.

Tree nuts are also common in noodles, curry, stir-fries, and rice dishes.

Tree nuts, particularly cashews, are also commonly used in plant-based or dairy-free cheese and cream, so it is important to always check the package and ingredients list of all foods your child is exposed to. 

Tree nuts, food labels and eating out

It is important to always check the package and ingredient list of all foods your child eats.

In Australia, allergens are bolded each time they appear in an ingredient list. Packaged foods may have a warning on the label that they "may contain traces of tree nuts." This means the food is made in a facility that also makes foods that contain tree nuts. Talk to your child’s doctor about whether they can eat these foods.

When eating out, always tell the staff that your child has a tree-nut allergy. This will help you find safe foods and avoid contamination. 

If you cannot confirm that food does not contain tree nuts, it is safest for your child to avoid it.

Talk to your child’s doctor about what foods containing tree nuts are safe if you are unsure.

Education

The most important thing you can do is support your child in avoiding tree nuts in their diet. You can also educate your child, family, and friends about allergies, reactions, and what to do in an emergency.

Parents of younger children must read ingredient lists and learn to find tree nuts in foods and drinks.

Older children can be supported in learning to read ingredient lists and find tree nuts in foods. 

This can help keep children safe and encourage them to be more independent and confident about their diet and health as they grow.

Resources and more information

The Australian Society of Clinical Immunology and Allergy (ASCIA)

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The Australian Society of Clinical Immunology and Allergy (ASCIA)

Biography
Provides resources including fact sheets, e-training and information on locating allergy specialists.
Related Links
Allergy & Anaphylaxis Australia - Your trusted charity for allergy support

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Allergy & Anaphylaxis Australia

Phone1300 728 000
Biography
Provides valuable updates and tips for dealing with food allergies.
Related Links
Food Standards Australia and New Zealand (FSANZ)

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Food Standards Australia and New Zealand (FSANZ)

Biography
Part of the Australian Government's Health portfolio and provides detailed information on food labelling.
Related Links
Last updated Tuesday 18th June 2024

Disclaimer

This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.


© Sydney Children’s Hospitals Network 2024