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Anaphylaxis

Frequently Asked Questions

This document has been developed by ASCIA, the peak professional body of clinical immunology/allergy specialists in Australia and New Zealand. ASCIA information is based on published literature and expert review, is not influenced by commercial organisations and is not intended to replace medical advice. For patient or carer support contact Allergy & Anaphylaxis Australia or Allergy New Zealand.

pdfASCIA PC Anaphylaxis FAQ 202487.71 KB

Q 1: What is anaphylaxis?

Anaphylaxis is the most severe type of allergic reaction and should always be treated as a medical emergency. Anaphylaxis requires immediate treatment with adrenaline (epinephrine), which is injected into the outer mid-thigh muscle. Delayed treatment can result in fatal anaphylaxis.

Anaphylaxis occurs after exposure to an allergen (usually to foods, insects or medicines), to which a person is allergic. Not all people with allergies are at risk of anaphylaxis.

Q 2: What are the signs and symptoms of anaphylaxis?

Signs and symptoms of anaphylaxis are potentially life threatening, and include any one of the following:

  • Difficult or noisy breathing.
  • Swelling of tongue.
  • Swelling or tightness in throat.
  • Wheeze or persistent cough.
  • Difficulty talking or hoarse voice.
  • Persistent dizziness or collapse.
  • Pale and floppy (in young children).

Q 3: What are the signs and symptoms of a mild to moderate allergic reaction?

In some cases, a mild to moderate allergic reaction may happen before anaphylaxis. Signs and symptoms of mild to moderate allergic reactions include:

  • Swelling of lips, face, eyes.
  • Tingling mouth.
  • Hives or welts.
  • Abdominal pain, vomiting - these are signs of anaphylaxis for insect allergy.

Q 4: What can make an allergic reaction more severe?

Allergic reactions can be made more severe by:

  • Exercise.
  • Heat.
  • Alcohol.
  • Food, including amount eaten and how it is prepared, especially for people with a confirmed food allergy.

These are known as co-factors.

Q 5: Why is identifying the cause of anaphylaxis important?

For people diagnosed as being at risk of anaphylaxis, identifying the cause (also known as a trigger) is a very important step in learning how to manage the condition:

  • A doctor will usually ask a series of questions that may help to narrow down the list of likely causes such as foods or medicines consumed that day, or exposure to insects.
  • A physical examination will then be done by the doctor who will also ask for a detailed history of symptoms to rule out conditions that can sometimes be confused with anaphylaxis, such as fainting or an epileptic seizure.
  • Allergy testing may be recommended if the doctor suspects an allergy is the cause of anaphylaxis. This will usually include a blood test for allergen specific immunoglobulin E (IgE) or skin prick testing (SPT), to help confirm or rule out allergy triggers.

Q 6: What allergy tests are not recommended?

There are many non-evidence based allergy testing methods offered either by unorthodox/alternative practitioners or through on-line testing services that are not recommended by ASCIA. These include VoiceBio, kinesiology, allergy elimination techniques and Immunoglobulin G (IgG) to foods. Although they claim to test for allergy, these methods are mostly unreliable and can lead to misdiagnosis and poor symptom control, often at significant cost to the patient.

Information about allergy testing is available at www.allergy.org.au/patients/allergy-testing

Q 7: Why does anaphylaxis need ongoing management?

Effective management of anaphylaxis saves lives. People at risk of anaphylaxis need ongoing management by a doctor. This should include:

  • Referral to a clinical immunology/allergy specialist - allergy.org.au/patients/locate-a-specialist
  • Identification of the trigger/s of anaphylaxis will include a detailed medical history and clinical examination followed by interpretation of allergy test results.
  • Education on avoidance of trigger/s is important for people with food allergy to avoid an allergic reaction. Advice from an experienced allergy dietitian may also be required.
  • A completed ASCIA Action Plan for Anaphylaxis to provide guidance on when and how to use an adrenaline injector (EpiPen® or Anapen®). Regular follow up with a clinical immunology/allergy specialist.

Q 8: Why is adrenaline used to treat anaphylaxis?

Adrenaline rapidly reverses the effects of anaphylaxis by reducing throat swelling, opening the airways, and maintaining heart function and blood pressure. Adrenaline injectors contain a single, fixed dose of adrenaline. They have been designed to be given by people without medical training, such as a friend, teacher, childcare worker, parent, passer-by or by the patient themselves (if they are not too unwell to do this).

If you or your child has been prescribed an adrenaline injector, it is important that you learn and practice how to use it, by using a trainer device. 

© ASCIA 2024

Content updated March 2024

For more information go to www.allergy.org.au/patients/about-allergy

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