The Management of Peanut Allergy

Peanut allergy is becoming ever more commonplace, both here in Europe and in the United States. The reason for this increase is not fully understood, but is in line with the general increase in all forms of allergy including asthma, eczema and hayfever. True food allergy affects over one million people in the UK.

Peanut allergy usually develops in children and is often lifelong, although some children have become tolerant of peanuts in the same way that children often learn to tolerate milk and eggs.

In any case where an allergic reaction to peanut is suspected the patient should be referred by their General Practitioner to an NHS allergy clinic for testing to confirm the diagnosis. Testing can be done by skin Prick Tests or blood tests.

A challenge test may be performed if the diagnosis of peanut allergy is in doubt. This is a safe procedure provided it is undertaken in a specialist allergy centre with experienced medical staff. Not only will this procedure confirm an allergic reaction, but it will also provide an opportunity to assess how severe an allergic reaction could occur if one accidentally came in contact with peanuts.

Skin Prick Testing involves making a tiny prick with a needle or lancet through a drop of allergen placed on the skin, usually on the forearm although sometimes the back may be used. If the test is positive the skin will become red and swollen with a blister-like "weal" in the centre. A positive result will be visible in 15-20 minutes. This form of testing is quite safe as only a tiny amount of allergen is introduced into the skin. The patient will need to stop taking antihistamines some days before the test; consult your doctor for advice.

Blood Testing involves measurement of the amount of IgE (Immunoglobulin E) specific allergy antibodies against peanut (and other allergy triggers) in the blood. The test is not affected by antihistamines or other drugs.

The Allergy Consultation with a qualified allergist is the most important part of the diagnosis of peanut allergy. It is possible to have a positive skin prick test or blood test, but not get symptoms when eating the food. Therefore without a positive history of an allergic reaction to the food you may not need to avoid it. The allergist will take a detailed history of the patient's reaction to any allergens then confirm the allergy with appropriate tests. Once peanut allergy has been confirmed then a management plan can be devised. This will need to take into account how severe a reaction has occurred. Not every patient with a peanut allergy will have an anaphylactic reaction.

Anaphylaxis is a severe generalised and potentially life threatening reaction to an allergen, where the whole body is affected.

Symptoms can include:

• Urticaria (nettle rash), itching flushing and weals
• Angiodema (swelling of lips, tongue and face)
• Nausea, vomiting and or diarrhea
• Abdominal Pain (stomach ache)
• Rhinitis (runny nose)
• Swelling of Larynx (voice box), hoarse voice, difficulty in swallowing
• Shortness of Breath wheeze, asthma and changed voice
• Falling Blood Pressure (may feel sense of doom)
• Change of Colour
• Dizzyness
• Loss of Consciousness

All patients with a known serious allergy should be easily identifiable. Small children should wear a Badge which states that they are peanut allergic, older children and adults should wear a Bracelet or Pendant with the same information, and that there is a risk. Companies that supply these are included in our Other Useful Organisations page.

If over a number of reactions only a mild response has occurred then it may be appropriate just to treat with an antihistamine. This decision would be made by the allergy specialist. All moderate or severe reactions should be treated as a medical emergency. Adrenaline (also known as Epinephrine) is the drug of choice. It should be administered as early as possible after the onset of symptoms. If in doubt, give adrenaline - and make sure that it is carried at all times. Where deaths occur, they are most frequently associated with either not using Adrenaline or with a delay in its use.

All patients receiving emergency Adrenaline should immediately be transported to hospital. Dial 999 and inform the controller that the patient is suffering from anaphylaxis. Should symptoms recur then a second dose of Adrenaline) may be required. Once in hospital other medication can be given as appropriate, including oxygen, fluids, antihistamines and corticosteroids. Even with initial adequate therapy with Adrenaline, delayed symptoms can occur, observation in an emergency facility is strongly recommended for 8 hours for life threatening anaphylaxis and 4 hours for milder systemic reactions.

Avoidance

Peanut (Arachis hypogaea) is a member of the bean family. Other members of this family include soya beans, lentils and garden peas. The allergic component of the peanut is the protein, which the body identifies as an alien substance and thus overreacts to. It is rare for a peanut allergic person to react to soya or other beans, but many peanut allergic people will also be allergic to other tree nuts, for example brazil or hazel nuts, which are genetically unrelated. Many commonly used foods contain peanut extracts, but although hydrogenated vegetable oil may occasionally have a peanut source, it is unlikely to cause an allergic reaction. Hydrogenated vegetable protein may rarely have a peanut source, and this may cause an allergic reaction in an extremely sensitive individual.

Peanuts are a very popular food and often included in confectionery, biscuits and Indian/Chinese/Asian/Thai food. Even with the most strenuous efforts it may not be possible to avoid them. Contaminations through the use of some production lines or the same utensils can occur. The food industry takes these issues seriously and many voluntarily label food as "contains peanuts" or "may contain trace of peanuts". The second statement is not always very helpful. In restaurants and "take aways" inclusion of peanuts is a potential hazard particularly where peanuts are a staple, but peanut butter has been found to be the "secret ingredient" in some dishes. Alcohol can potentiate an allergic reaction, making it stronger and occur more quickly, this does not mean that one cannot drink, but if a reaction occurs then it must be dealt with immediately. No one can guarantee complete avoidance of any food allergen, all food which you do not prepare yourself must be considered somewhat suspect, but with the correct medication (Adrenaline or antihistamines) the risk incurred is minimal provided you use it immediately and then go straight to hospital.

All of the major supermarket chains in this country provide "Free From" lists, it is possible to get a list of own brand foods which do not contain peanuts, but companies do change the ingredients in processed foods, sometimes without stating that this has occurred.

It is best to read the list of ingredients on processed foods, even if you have eaten it without problems before.

Peanut Oil, Groundnut Oil and and Arachis Oil

Researchers have concluded that refined peanut oil will not cause allergic reactions for the overwhelming majority of peanut allergic individuals, and if anyone does suffer a reaction it is likely to be mild. Unrefined (crude) peanut oil should be avoided by peanut allergic people. Refined peanut oil appears to carry a low or no risk. But it is up to individuals themselves or parents to weigh the evidence and make up their own minds.

Skin Preparations

Some skin preparations may contain arachis (peanut oil).A number of researchers have theorised that there might be a link between the use of these creams and the development of peanut allergy in some children. However there is no published evidence of experiments or studies to support this theory, therefore it must be considered unproven, though possible. It may be because tiny residues of peanut protein are present; not enough to cause allergic reactions but enough, in some cases to "set up" an allergy to peanuts. Research is underway to resolve this theory, but meanwhile in families where there is a known history of allergy you may prefer to avoid skin preparations and cosmetics known to contain arachis/peanut oil.

Anaphylaxis in Schools and/or Nurseries

Every allergic child should have an individual management plan, which should be devised through the collaboration of an Allergy Specialist, GP, School Nurse, parents and school nursery staff including teachers/dinner ladies. A Child Specific Protocol is available from Allergy UK for this purpose (01322 619898, or see www.blossomcampaign.org). The Department of Education and Employment and Department of Health have produced a guide to "Supporting Pupils with Medical Needs in School". Freecopies of this document can be obtained from:

DFES Publications Centre (Department for Education and Skills)
P O Box 5050
Sherwood Park
Ansley
Notts
NG15 0DJ
Tel: 0845-602-2260
Fax: 0845-603-3360

The management plan should include details of the child's allergies, their symptoms, how to recognize a reaction and what to do if symptoms should occur. Teachers and support staff should know the location of the child's Adrenaline injector (if prescribed) and should be able to use it, and understand the importance of calling for help.

If the child is old enough and happy to self administer Adrenaline, this should be encouraged. It may be decided to have a peanut and nut free environment, some schools and nurseries have chosen this option as it reduces the potential risks, especially for very small children. But it is clear from many experiences with allergic children that they are quite capable of making it very clear that they are allergic and they will refuse to eat anything unless they have checked with an adult.

Adults

Adults are responsible their own allergy, and can make informed decisions about what constitutes a reasonable level of risk when you choose a processed food or eat out. You are in a much better position than someone who has not had a confirmed diagnosis of their allergy

Always carry your auto-injector(s). If you have to use your Adrenaline injection then you must go to hospital for observation.

Be prepared to be firm when discussing your allergy in restaurants/bars etc., this is called being aggressively polite! For many people an allergy just means a rash not a potentially life threatening condition. Use your Medic Alert emblem to get peoples attention if necessary. State that you wear this because your reaction can be very severe. If you do have a reaction in a public place, you must inject yourself first and delegate someone to call an ambulance. If you must go to the toilet because of vomiting or diarrhoea, do not go alone, take someone with you.

YOU MUST ASSUME THAT NO ONE WILL KNOW WHAT TO DO IN AN EMERGENCY AND BE RESPONSIBLE FOR YOURSELF. DO NOT GO OFF QUIETLY BY YOURSELF BECAUSE YOU ARE EMBARRASSED.

Translation Cards

We have produced cards in most European languages, which are useful if you are travelling in a country where you may not be entirely sure of the best way of describing your allergy. If you wish to purchase a set you can call the Helpline on 01322 619898 stating what allergen and what language you need the information in. The cost per language is £15. The Helpline is open Monday to Friday 9am-5pm. Further information is available here.

Allergy Desensitization

Recent trials with peanut-allergic children have shown promising results in using small doses of peanut to produce 'tolerance', allowing the child to eat a moderate dose of peanuts safely. There is still much work to do before this treatment becomes generally available. You should never try desensitization at home.

Anthistamines:

There are a number of fast acting non-sedating antihistamines available from your local chemist without prescription. Please seek advice from your pharmacist.

Updated 7/2009