The signs and symptoms of anaphylaxis are listed below. Make sure you know what these symptoms are so that you know when to use your Jext®. These symptoms can develop rapidly within minutes, or over a period of hours.

Only a few of the following symptoms may be present, however some can be life-threatening.

  • Itchy rashes
  • Swelling lips
  • Dizziness
  • Racing heart
  • Shortness of breath
  • Feeling of impending doom

If you experience any or all of these symptoms, you should use Jext® and call 999 in the UK, or 112 in Ireland, ask for an ambulance and say ‘anaphylaxis’. Always use your medicine as you were instructed by your doctor. It is important to remember that the pattern of symptoms you experience may be different from previous reactions.


The most common causes of anaphylaxis are food and venom (wasp stings).

Common food triggers are:

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

Anaphylaxis can also be triggered by:

  • Venom from stinging or biting insects. Wasp and bee venom are the most common insect allergens. On rare occasions stings from hornets and bumble bees can also cause allergic reactions
  • Medicine – most commonly antibiotics, aspirin or ibuprofen
  • Latex
  • Exercise

Sometimes the cause may be unknown.


Adrenaline is the drug of choice for first-line treatment of anaphylaxis because it works quickly to reverse the symptoms of an anaphylactic reaction.

When adrenaline is injected into the muscle of the thigh it acts quickly to constrict blood vessels, which helps to stop swelling around the face and lips, and relaxes the lungs, which improves breathing. Adrenaline also stimulates the heart, and helps raise lowered blood pressure.

The sooner the injection is given the better and you should seek professional medical assistance immediately after using your Jext®. You should be prepared to administer a second Jext® after 5 -15 minutes if there is no improvement or if original symptoms return.

Each Jext® can only be used once. It is recommended you carry two Jext® in case you do need a second dose.