Anaphylaxis - Fast Facts
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.
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), injected into the outer mid-thigh. Delayed treatment can result in fatal anaphylaxis.
Adrenaline is a natural hormone released in response to stress. When injected, 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, and have been designed to be given by non-medical people, including the person themselves, if they are well enough.
Signs of anaphylaxis 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)
- Abdominal (stomach) pain, vomiting – these are signs of anaphylaxis for insect allergy
When a person has anaphylaxis, they should NOT stand, walk, or be held upright, even if they appear to have recovered. Their blood pressure can drop rapidly, which reduces blood flow to the heart. Laying the person flat will help blood flow to the heart which improves blood pressure. Standing or walking can make anaphylaxis worse by causing blood pressure to drop.
In some cases, a mild to moderate allergic reaction may happen before anaphylaxis. Signs of mild to moderate allergic reactions include swelling of lips, face or eyes, hives or welts, tingling mouth.
ASCIA Action Plans for Anaphylaxis and ASCIA First Aid Plans for Anaphylaxis are available on the ASCIA website www.allergy.org.au/hp/anaphylaxis/ascia-action-plan-for-anaphylaxis
© ASCIA 2023
Content updated June 2023
For more information go to www.allergy.org.au/anaphylaxis
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