About anaphylaxis

All allergic reactions are caused by the immune system in the body. The immune system’s job is to fight off things that could make a person ill.

However, in some people the immune system makes mistakes and thinks that a type of food or another substance is harmful. The body starts to fight off this substance or allergen – and the person has an allergic reaction.

Sometimes, an allergic reaction causes annoying things like
itchiness or a runny nose. But sometimes, it can cause more
serious problems like a ‘puffy’ face, a swollen tongue, and finding it hard to breathe. This severe type of an allergic reaction is called an anaphylactic reaction.


The signs and symptoms which warn that an anaphylactic reaction is starting are listed below.

  • Itchy rashes
  • Swelling lips
  • Dizziness
  • Racing heart
  • Tightening of the throat
  • Difficulty in breathing

Make sure you know what these symptoms are so that you know when your child needs to use their Jext®. These symptoms can develop very quickly (within minutes), or more slowly (over a number of hours).

Your child may have only a few of the symptoms, however some of them can be very serious.

If your child experiences any or all of these symptoms, they should:

  • Call for help
  • Use their Jext®, or ask someone else to give it to them
  • Use a phone to dial 999 in the UK, or 112 in Ireland, ask for an ambulance and say ‘anaphylaxis’. Or ask somebody else to make the call

It is important to remember that the symptoms your child experiences may be different from previous reactions.


Get to know the ‘Allergens’

It is important that you and your child know which thing or things caused them to have an allergic reaction in the past. This is because they must try to avoid having a reaction again in the future…

Common food allergens are:

  • Peanuts
  • Tree nuts
  • Fish and shellfish
  • Fruit
  • Dairy products such as milk and eggs

Anaphylaxis can also be triggered by:

  • Wasp or bee stings
  • Medicines such as antibiotics
  • Materials such as rubber
  • Exercise

Sometimes the cause may be unknown.


Jext® adrenaline auto-injector

A doctor has given your child Jext® because their body reacted badly to something in the past, such as a type of food or an insect sting. In other words, they had an allergic reaction to something.

Jext® contains a liquid called adrenaline. This is a medicine which Jext® injects into your child’s body. It works quickly to reverse the symptoms of an anaphylactic reaction, whilst your child waits for an ambulance.

Jext® is easy to use, and your child won’t see the needle going into their body.

If your child doesn’t feel any better within 5-15 minutes of using Jext®, they may need to use a second Jext®. Each Jext® can only be used once. It is recommended they carry two Jext® in case they do need a second dose.