Primary Care Liaison

Allergic reaction - Anaphylaxis

  • The following pre-referral guideline covers allergic reactions and a history of anaphylaxis for children of all ages.

    This guideline does not cover acute management.

    Please call an ambulance if concerned (000) and see  What is an allergy or  Clinical practice guidleines - Anaphylaxis  for more details on history taking and acute management.

    See also specific fact sheets/ guidelines on Food Allergy, Drug Allergy and Latex Allergy

    When to refer

    All suspected allergies when

    • ALWAYS refer confirmed or suspected anaphylaxis to the RCH Department of Allergy and Immunology.
    • Clinical history or specific IgE blood testing indicates that a child may be growing out of moderate to severe allergy and challenge testing is required.

    Suspected food allergy when

    • Specific IgE blood test is positive.
    • Suspected IgE or non IgE mediated food allergy is causing one of the following:
      • Severe eczema (or asthma - rare).
      • Failure to thrive.
      • Dysphagia.
      • Reflux/ GI symptoms.

    Drug allergy when

    • Challenge testing is required to identify a safe drug for future use (e.g. anaesthetic or a patient with a history of severe penicillin allergy).
    • There is no other drug alternative (e.g. insulin, chemotherapy or penicillin) and desensitisation is required to get the child onto the drug without causing a severe allergic reaction (transient tolerance).

    Stinging insect allergy when

    • Patient is identified as a potential candidate for venom immunotherapy (e.g. confirmed anaphylaxis to honey bee or wasp). Stinging ant may soon be available too

    The following referrals will not be accepted

    • For allergy screening if there is no clear history of allergic reaction
    • Drug allergy if the reaction was mild, there are alternative drugs available and avoidance is an option for management (e.g. ceclor reactions)
    • Large local reactions or mild systemic reactions to stinging insects
    • Suspected food intolerance- contact the Gastroenterology department

    Pre-referral assessment/treatment

    Initial work-up

    History

    • History of atopy (e.g. eczema/asthma).
    • Family history of allergic disease.
    • History of allergic reaction -
      • Food - food type, amount, form ingested in, time to reaction, nature of reaction, has the food been taken without reaction in the past? Has it been taken since?
      • Drug - drug type, amount, form ingested in, nature or reaction, previous or subsequent exposure?
      • Stinging insect - circumstances, insect prevalence, nature of the bite or sting, presence of a stinger or recognisable insect, previous and subsequent sting history and the nature of the reaction.
      • Relation of reaction to exercise.
    • Nature of any food allergy -
      • IgE mediated (hives, angioedema, respiratory/CVS).
      • Non IgE mediated (gut or eczema).
    • Also read notes below for specific allergies.

    Diagnostics

    • IgE blood test for specific allergen if history indicates.
    • Only blood test for food allergy if IgE mediated (not useful for non IgE mediated).
    • Skin Prick Test NOT recommended for food, drug or latex allergy (small chance of a systemic reaction). 

    Food allergy

    The most common allergens in children are peanuts, tree nuts (e.g.cashews), eggs, cow's milk, fish and shellfish, wheat, soy, sesame, latex, certain insect stings and medications.

    Reactions to other foods do occur, but are less common (e.g. rice).

    Food allergy (caused by an immune mechanism) is different to food intolerance (non-immune). Examples of intolerance include lactose intolerance due to absence of lactase enzyme in GI tract, scromboid fish poisoning, MSG, erythema from strawberries, citrus or tomatoes.

    The majority of food allergies are not life-threatening.

    Emphasize that the majority of food allergies are not dangerous.

    Avoidance of specific types of food is not recommended if the child has never been exposed or never had a reaction to the food. Parents should introduce small amounts of food and observe.

    If history is positive and specific IgE blood test is negative, GP may perform a supervised food challenge, however be aware that 2% will react and have emergency management equipment available.

    Drug allergy

    Penicillin is the most common cause of serious allergic drug reactions in children.

    • Take history of drugs taken safely in the past that have not caused allergic reactions.
    • Common agents are penicillin, insulin, non steroidal anti-inflammatories, aspirin, local anaesthetic and non-penicillin antibiotics.
    • Penicillin IgE blood test can be used to investigate, however this is only of value if the reaction is IgE mediated hypersensitivity.
    • In all cases, discontinue the drug promptly.
    • Alternative antibiotics are available on the market - look for one of equal efficacy.
    • Possible amoxicillin or penicillin-derivative reactions may require avoidance of broad class of antibiotics.
    • Paracetamol can be used as an alternative to aspirin.

    Latex allergy

    • Look for presence of risk factors for latex allergy (e.g. repeated surgical procedures, spina bifida, VP shunt, repeated catheterisation, health care worker.
    • Latex allergic patients may describe oro-pharyngeal itching and swelling when eating banana, avocado, potato, tomato, chestnut or kiwi fruit.
    •  Provide advice on avoidance of latex exposure e.g. dental procedures, condoms, balloons.

    Non-emergency management 

    • Prescribe Epi-Pen.
    • Educate on correct use of Epi-Pen.
    • Provide Anaphylaxis Action Plan ( www.allergy.org.au)
    • Alleviate alarm.
    • Support parent in school/day care communication.
    • Ensure any asthma is well controlled.
    • Educate on strict avoidance of allergen.
    • Do not attempt to perform a challenge to the allergen in doctor's surgery.
    • Consider use of a MedicAlert bracelet (especially for drug or latex allergy).

    Mild-moderate reactions (including contact reactions)

    • Antihistimine +/- oral steroid tablets. Carry at all times in order to be prepared for inadvertent exposure.
    • Loratidine (Claratyne) and certirizine (Zyrtec) are suitable for children over 1 year old.
    • Also see the allergen specific management notes above.

    Resources

    References

    The Asthma Management Handbook (2006). Asthma and Allergy (pp57-63) National Asthma Council Australia.

    Australasian Society of Clinical Immunology website www.allergy.org.au.

    ASCIA Education Resources.

    Copyright and Disclaimer

    Copyright 2006, Royal Children's Hospital (RCH) Victoria, Australia. Adapted with permission from Children's Hospital and Regional Medical Center, Seattle, WA, USA.

    The RCH and Children's Hospital and Regional Medical Center are not responsible in any way for application of the procedures or guidelines to patient care at your facility. They are guidelines only and your professional judgment must always prevail. Guidelines may not be reproduced without permission. RCH Kids Connect - Primary Care Liaison. www.rch.org.au/kidsconnect

    These guidelines were developed by specialists at the Royal Children's Hospital and reviewed by a working group of metropolitan and rural general practitioners in Victoria. Last reviewed in October 2013 by RCH Allergy and Immunology Department and Primary Care Liaison.