Signs and symptoms of Anaphylaxis

Signs and symptoms

The symptoms of anaphylaxis usually start between 3 and 60 minutes after contact with the allergen. Less commonly, they can occur a few hours or even days after contact.

When your casualty has an anaphylactic reaction, they may feel unwell or dizzy or may faint because of a sudden drop in blood pressure.

Narrowing of the airways can also occur at the same time, with or without the drop in blood pressure. This can cause breathing difficulties and wheezing. 

Your casualty may also experience any of the symptoms below:

  • Swollen eyes, lips, hands, feet and other areas 
  • A strange metallic taste in the mouth 
  • Sore, red, itchy eyes 
  • Changes in heart rate 
  • A sudden feeling of extreme anxiety or apprehension 
  • Itchy skin or nettle-rash (hives)
  • Unresponsiveness due to very low blood pressure
  • Abdominal cramps, vomiting or diarrhoea
  • Nausea and fever 

Your casualty would not necessarily experience all of these symptoms.

Adrenaline is the gold standard in the treatment of anaphylaxis, and its administration should not be delayed. 
In a first aid situation, adrenalin will normally be delivered by an auto-injector. If available, an injection of adrenaline should be given as soon as possible. If after 5 minutes the casualty still feels unwell, a second injection should be given. This should be given in the opposite thigh. A second dose may also be required if the symptoms reoccur. When treating a potential anaphylaxis casualty, it should be noted that there are NO contraindications for the use of adrenaline.

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