What is Anaphylaxis

Anaphylaxis is a severe allergic reaction that is rapid in onset and can be life-threatening. Mild symptoms can progress rapidly to a severe reaction. Anaphylaxis must be treated as a medical emergency requiring immediate medical attention. Prompt treatment with injected adrenaline is required to halt the progression of the reaction.1

Symptoms of anaphylaxis vary, but can include hives, itching, flushing, and swelling of the lips, tongue, and roof of the mouth. The airway is often affected, resulting in tightness of the throat or chest and difficulty breathing. These reactions can also be accompanied by chest pain, low blood pressure, dizziness and headaches.2

Asthma and Anaphylaxis 3

Asthma is a chronic inflammatory disease of the airways. People with asthma experience a narrowing of the airways due to inflammation in the lungs, which blocks the flow of air into and out of the lungs. Asthma is most easily recognised by the following symptoms:

  • Wheezing (noise when breathing out).
  • Persistent cough, especially at night.
  • Difficulty breathing and shortness of breath.
  • Tightness and heaviness in the chest.
  • Wheezing or coughing with exercise (exercise induced asthma).

Symptoms such as wheezing, difficulty breathing and persistent cough can also present with anaphylaxis and sometimes you may be unsure if it is asthma or anaphylaxis.

Asthma, food allergy and high risk of anaphylaxis (severe allergic reaction) frequently occur together. This increased risk of anaphylaxis in asthmatic individuals highlights the importance of managing your asthma well as part of your anaphylaxis risk management.

If you have sudden onset of breathing difficulty soon after an insect sting or exposure to food or medication you may be experiencing anaphylaxis, not just asthma. It is important to note that;

  • The progression and severity of allergic reactions can be unpredictable.
  • Most food related allergic reactions start within 20 minutes or up to 2 hours after exposure.
  • Mild to moderate symptoms of allergy may or may not present before symptoms of anaphylaxis.

If you are unsure if you are experiencing anaphylaxis or asthma, always give adrenaline auto-injector first, then asthma reliever puffer. Refer to the ASCIA Action Plan for Anaphylaxis here for step by step instructions.

What causes anaphylaxis? 2.4

Anaphylaxis can be triggered by a number of allergens including:

How is anaphylaxis treated?

When a person is experiencing anaphylaxis, administering adrenaline as soon as possible can be life-saving. When adrenaline is injected, it helps to alleviate wheezing and shortness of breath, maintains your blood pressure and helps prevent shock, relieves swelling and itching or rashes, and has many other effects that relieve the anaphylactic symptoms.4

According to Allergy & Anaphylaxis Australia, research has shown that fatalities more often occur away from home and are associated with either not using, or a delay in using, adrenaline treatment. That’s why it is so important to be prepared by carrying your EpiPen® adrenaline auto-injector at all times.5

Being prepared means having a plan to:

  • Avoid known allergens
  • Know what symptoms to watch for
  • Use an EpiPen® Auto-Injector if a life-threatening (severe) allergic reaction occurs
  • Get emergency help right away

1. Lieberman P, Nicklas RA, Oppenheimer J, et al. The diagnosis and management of anaphylaxis practice parameter: 2010 update. J Allergy Clin Immunol. 2010; 126(3):477-480.e1-42.
2. Simons FE. Anaphylaxis. J Allergy Clin Immunol. 2010; 125(2)(suppl 2):S161-S181.
3. Australasian Society of Clinical Immunology and Allergy (ASCIA). Asthma and Anaphylaxis. Available at: www.allergy.org.au 
4. Simons FER et al. WAO Journal 2011; 4:13-37
5. Allergy & Anaphylaxis Australia (AAA). What is Anaphylaxis? Available at: www.allergyfacts.org.au.