What is an anaphylactic reaction?

Anaphylactic Reaction

What is an anaphylactic reaction?Anaphylactic Reaction

Anaphylactic reactions are symptoms due to severe allergies, which cause serious and sudden illness that may result in death. They occur due to an overreaction of the immune system to certain substances or triggers, which are normally otherwise harmless.

Some common triggers include:

  • Peanuts, fish, milk eggs and other food triggers
  • Bee and wasp stings, ant bites and other insect bites and stings
  • Medicines such as penicillin and aspirin and other medications

On some occasions, a person’s trigger may not be identified.

What are the signs of an anaphylactic reaction?

Anaphylaxis is usually rapid, occurring between 20 minutes to 2 hours after being exposed to the trigger. The signs may be subtle at first but then can become more severe.

Signs of an anaphylactic reaction can include any of the following:

  • Swelling of the tongue and throat
  • Ongoing cough and wheezing
  • Difficulty breathing which can manifest in loud breathing
  • Dizziness or collapse
  • Abdominal pain or vomiting
  • In young children, pallor, lethargy

Treatment for anaphylactic reactions

Anaphylactic reactions are serious medical emergencies. Emergency treatment can be followed using the instructions on individual ASCIA Action Plan for Anaphylaxis or First Aid Anaphylaxis Plan.

  1. Lay the person flat – do NOT allow them to stand or walk
  2. Give adrenaline injector (EpiPen® or AnaPen®)
  3. Phone ambulance – 000
  4. Phone family/emergency contact
  5. Further adrenaline may be given if there is no response after 5 minutes
  6. Transfer the person to the hospital for at least 4 hours of observation from the time of the last dose of adrenaline

The adrenaline (epinephrine) autoinjector (EpiPen® or AnaPen®) should be given first. This includes people with asthma or breathing difficulty, even if no skin signs are present.

Conduct CPR at any time if the person is not responding and not breathing normally.

Why is adrenaline (epinephrine) used to treat anaphylactic shock?

Adrenaline acts quickly on neurons to cause various systemic mechanisms for reducing the symptoms of anaphylactic shock. Some of these include:

  • Causing throat and lungs to relax allowing for breathing
  • Increasing blood pressure and blood flow around the body
  • Decreasing inflammation of the skin, and reducing redness, swelling and pain

How to prevent of anaphylactic reactions

The best way to prevent anaphylactic shock is to avoid known triggers. It is also important to tell the people around you about your allergy, including when eating out for food allergies or at the workplace. Your doctor may also refer you to an allergy specialist for allergy testing. In some cases, desensitisation to the identified allergen may be possible.

Where to get help