What is anaphylaxis? – allergypunk

What is anaphylaxis?

Anaphylaxis is the most severe, rapidly progressive allergic reaction and is life threatening. 

A reaction can develop within minutes of exposure to the allergen, but with planning and training a reaction can be treated effectively by using an adrenaline injection (EpiPen®/EpiPen®Jr or Anapen®/Anapen® Jr). An important aspect of anaphylaxis management is prevention by avoiding the cause.

However, deaths have occurred and anaphylaxis is a medical emergency requiring a rapid response. Call 000 



Mild to moderate allergic reaction can include:

  • swelling of the lips, face and eyes;
  • hives or welts;
  • tingling mouth; and
  • abdominal pain and/or vomiting (these are signs of a severe allergic reaction to insects).

Anaphylaxis (severe allergic reaction) can include:

  • difficult/noisy breathing;
  • swelling of tongue;
  • swelling/tightness in throat;
  • difficulty talking and/or hoarse voice;
  • wheeze or persistent cough;
  • persistent dizziness or collapse; and
  • pale and floppy (young children).
  • Losing consciousness
  • Sudden drop in blood pressure

Symptoms usually develop within 10 minutes to several hours after exposure to an allergen, but can appear within a few minutes

Emergency medical Action Plan 

Emergency action - symptoms poster

Anaphylaxis is a severe allergic reaction that is life threatening. Usually two systems of the body are involved such as the respiratory and circulatory system. An example of a reaction with these two systems would be difficulty breathing (respiratory) and drop in blood pressure (circulatory).



Anaphylaxis occurs when a person comes in contact with an allergen through:ingestion, bites, stings, and contact. This can be even a very small amount. Certain foods and insect stings are the most common causes of anaphylaxis.

 >Food allergies. Any food can cause an allergic reaction. Eight foods cause ninety-five per cent of food allergic reactions in Australia and can be common causes of anaphylaxis:

  • peanuts;
  • tree nuts (i.e. hazelnuts, cashews, almonds, walnuts, pistachios, macadamias, brazil nuts, pecans, chestnuts and pine nuts);
  • eggs;
  • cow's milk;
  • wheat;
  • soy;
  • fish and shellfish (e.g. oysters, lobsters, clams, mussels, shrimps, crabs and prawns); and
  • sesame seeds.

>Bites and stings. Some insect stings, particularly bee stings but also wasp and jumper jack ant stings, tick bites

>Medications Antibiotics and anaesthetic drugs


>Exercise induced anaphylaxis (rare) which generally occurs during exercise, and three to four hours after eating a specific food.

>Idiopathic i.e. unknown (rare) occurs without a specific identifiable reason, sometimes called idiopathic anaphylaxis.

All forms of anaphylaxis are life threatening.



Adrenaline given as an injection into the muscle of the outer mid-thigh is the most effective first aid treatment for anaphylaxis.

Children or adults diagnosed as being at risk of anaphylaxis are prescribed Adrenaline Autoinjector in an emergency. The two most common brands of Adrenaline Autoinjectors available in Australia are EpiPen® and Anapen®300.

 Anaphylaxis is a medical emergency. Call 000 immediately, even if treated with medication.

You will then be observed in a hospital by trained doctors for at least 6 hours

Does anaphylaxis disappear after one shot of epinephrine?

That depends on the condition of the person who is experiencing anaphylaxis. Sometimes only one shot is needed, other times a shot of epinephrine is needed every 15 minutes and until symptoms lessen. Sometimes, after a few hours, a secondary reaction occurs (called bi-phasic) then additional shots of epinephrine is needed until symptoms have stopped.



There is currently no cure for anaphylaxis. The only treatment for anaphylaxis is avoidance. Avoidance of the allergen is the key to prevention. If a person is allergic to a food then it is recommended to avoid that food, even trace amounts.

If the allergy is derived from the environment; for example pollen, insect stings, and chemicals; then it is important to stay away from that allergen. It is not safe to assume anaphylaxis will not occur so always be prepared for treatment by carrying medication with you at all times. It is generally recommended to carry 2 adrenaline auto-injectors.


Preventing an allergic reaction or anaphylaxis is very important. Ways you can prevent an allergic reaction or anaphylaxis include:

  • Knowing and avoiding the causes.
  • Not allowing food sharing or swapping.
  • For teachers: only giving foods approved by the parents or foods you have witnessed the child eating before.
  • For teachers: using non-food treats where possible, but if food treats are used in class give only those provided by the parents. (Encourage parents to provide a container of safe treats from home).
  • Practising routine hygiene and good food safety practices. Children and staff should always wash their hands after play and before eating, and tables should be wiped down after eating.



Each reaction can be different, even for the same person, for instance some reactions may or may not might involve hives.

Always carry your emergency medication, generally recommended to carry adrenaline auto-injectors

Can progress quickly and requires a rapid response

Can be fatal if adrenaline not given in time

Anaphylaxis can occur from cross-contact or contamination

Even a tiny amount of allergen can cause anaphylaxis 

If an adrenalin auto-injector is used, always call an ambulance by phoning 000.


Above information is sourced from ASCIA and the Royal Children's Hospital

If you suspect anaphylaxis call 000








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