Peanut and tree nut allergy
Usually, a child who is allergic to peanuts or other nuts will only have a mild reaction. However, peanuts and tree nuts (especially cashews) are a common cause of anaphylaxis. Anaphylaxis is the most severe form of an allergic reaction, and is life threatening.
Allergies to peanuts and tree nuts are more common in people who have other allergic conditions, such as hay fever, asthma and eczema. Children with a nut allergy may also be allergic to other foods such as milk, eggs, shellfish and other types of nut.
Peanut and tree nut allergies are most common in young children, but allergies can develop at any age, even in adulthood.
Signs and symptoms of nut allergies
Mild to moderate allergic reaction
An allergic reaction will include one or more of these symptoms, and it is possible that a number of them will happen at the same time:
- hives, welts or wheals (a red, lumpy rash, like mosquito bites)
- a tingling feeling in or around the mouth
- stomach pain, vomiting and/or diarrhea (loose poo)
- facial swelling.
The first time your child has a mild to moderate allergic reaction to peanuts or other nuts, take them to the GP. The doctor will confirm whether your child had an allergic reaction and advise you how to treat the reaction next time it happens. If the reaction was moderate, you may be referred to an allergy specialist.
Severe allergic reaction (anaphylaxis)
A severe allergic reaction involves a person's breathing and/or circulation (heart and blood). Any of the following symptoms, as well as one or more of the above symptoms of a mild to moderate allergic reaction, indicates your child is having an anaphylactic reaction:
- difficulty with breathing and/or noisy breathing
- wheeze or persistent cough
- swelling of the tongue
- swelling and/or tightness in the throat
- difficulty talking or hoarse voice
- loss of consciousness or collapse
- becoming pale and floppy (infants/young children).
Call an ambulance immediately if your child has symptoms of anaphylaxis.
Diagnosis of nut allergies
If your child has a reaction to peanuts or other nuts, a doctor will ask you a series of questions to find the cause of the allergy. For example, they will ask you what foods your child eats, if your child takes any medicines, and if your child may have come into contact with any stinging insects. These questions will help to rule out other conditions that can sometimes be confused with food allergies.
If your child does have a possible nut allergy they will need a blood test, called a RAST allergy test, or a skin prick test. Your child may be tested to see if they are allergic to other foods too.
Treatment for nut allergies
Once your child has a confirmed nut allergy, your doctor will prepare an action plan for your child. The action plan will be green if no adrenaline autoinjector is required, and red if one is required. Make sure you understand the action plan well and ask if there is anything you're not confident about.
The best treatment for peanut or tree nut allergy is prevention, which means avoiding the specific nuts completely. Nuts are hard to avoid because many foods are made in factories that may have used peanuts or nuts in other foods. Even in tiny amounts, peanuts and nuts can cause symptoms.
It is important to teach your child not to share or swap food with others, and to always wash their hands before eating.
If your child has been diagnosed as having anaphylactic reactions to nuts, then they will need to have an adrenaline autoinjector (e.g. an EpiPen) available at all times. See our fact sheet Allergic and anaphylactic reactions.
Avoiding peanuts and tree nuts
People with any nut allergy should avoid all types of nuts until advised otherwise by their allergy specialist.
By law, any product that may contain peanuts or tree nuts (or even tiny amounts of these nuts) must include that information on the food labelling. Some manufacturers will label their products as possibly containing traces of nuts due to other foods that are processed at the same facility.
Refined nut oils (not cold pressed) have been shown to be safer for children with allergies. However, it is difficult to guarantee the oil is sufficiently refined and all traces of the nut protein have been removed. In general, it is safest to avoid all nut oils if your child has a severe allergy.
The following list includes common sources of peanuts and tree nuts:
- baked goods such as cakes and slices
- biscuits and cookies
- breakfast cereals
- Christmas cakes and puddings
- chocolate and chocolate spreads
- curry pastes
- dips and flavoured cheeses
- dried fruit and trail mixes
- energy mixes or trail mix
- fruit crumble mix
- flavoured coffee syrups
- ice cream
- muesli bars and health bars
- natural flavourings
- nougat, fudge, praline, rocky road and Turkish delight
- pasta sauces and pesto
- restaurant and takeaway meals – especially Asian, African and Indian meals
- salads and salad dressings
- vegetarian meals.
However, note that this list is not complete and ingredients in food products may change, so always check food labels each time you purchase a product.
Sometimes, nut products or oils are used in products your child may have contact with. Be careful with animal and bird feeds, cosmetics and massage oils, and the progesterone cream called prometrium (which is derived from peanuts). Arachis hypogaea is the scientific name for peanut, and peanut oil is sometimes listed as arachis oil.
Nut allergies and school/child care
Organise a meeting with staff caring for your child at their school, kindergarten or childcare centre. Staff will work with you to develop a management plan for your child, detailing the risks and how they will manage these on a day-to-day basis.
- Your child should take their own nut-free food with them to school. They should know never to swap food with other children.
- Where childcare centres and kindergartens have eating and food preparation in a communal area, make sure staff know that your child has a nut allergy.
- Make sure that anyone caring for your child understands that absolutely no nut products are to be given to your child. If you are not sure about the contents of a product, ask your GP or allergy specialist.
Key points to remember
- Peanut and tree nut allergies are common and can develop at any age.
- Symptoms can be mild or severe. Anaphylactic reactions are life threatening.
- Call an ambulance immediately if your child has symptoms of anaphylaxis.
- Always check labels of foods for traces of any peanuts or nuts.
- Teach your child not to share or swap food with others, and to always wash their hands before eating.
For more information
- Kids Health Info fact sheet: Allergic and anaphylactic reactions
- The Royal Children's Hospital Allergy and Immunology department: Parent information sheets
- Australasian Society of Clinical Immunology and Allergy (ASCIA)
Common questions our doctors are asked
What is a safe age to first feed my baby peanuts or other nuts? Should I hold off until he is older to avoid allergies?
Do not hold off introducing foods like peanuts to your baby – studies have shown that introducing foods that may cause an allergy within the first 12 months of life may in fact reduce the chance of your baby developing a food allergy. Talk to your Maternal Child Health Nurse or GP about how to introduce solid food, including allergens. If your baby has an allergic reaction, stop feeding them the food you were giving them and seek medical advice. If your baby shows signs of anaphylaxis, call an ambulance immediately.
Will my child outgrow their nut allergy?
There is a good chance your child will outgrow their allergy: around 20 per cent of children outgrow their peanut allergy by the time they are teenagers, while around 10 per cent will outgrow a tree nut allergy.
Your doctor will work out if your child has grown out of their nut allergies using a combination of allergy testing and food challenges. Food challenges should only be performed by experienced medical staff in specialised facilities.
Your allergy specialist may recommend a desensitisation processes, which may help your child's body increase its tolerance to the trigger. This is done in a controlled environment under close supervision.
My child has a peanut allergy but the school hasn't banned nuts. What can I do about this?
Banning foods that contain the peanuts is not the best way to prevent allergic reactions, for a number of reasons. Banning will not succeed in creating a perfect allergy-free zone. Other parents may not comply with the ban, or be confused by product labelling, and staff and children can become complacent about not sharing food or checking that they are nut-free. It is best to educate your child about not sharing food with others, and washing their hands before they eat.
Developed by The Royal Children's Hospital Allergy and Immunology department. We acknowledge the input of RCH consumers and carers.
Reviewed July 2018.
Kids Health Info is supported by The Royal Children’s Hospital Foundation. To donate, visit www.rchfoundation.org.au.