What is anaphylaxis?

Anaphylaxis is a severe and potentially life-threatening allergic reaction. An allergen can be any food or substance that the body identifies as foreign. The body’s natural defence system then triggers a reaction.

Symptoms can occur within seconds or minutes of coming into contact with an allergen. Symptoms can also occur several hours after exposure but this is rare.

What causes allergic reactions?

Common food allergens are:

• nuts
• milk
• eggs
• shellfish.

Or there are common reactions to medicines such as: 

• antibiotics; for example, penicillin
• aspirin
• general anaesthetic.

Other common allergens include bee and wasp stings and latex.

What are the signs and symptoms of an allergic reaction?

Individuals that suffer from an anaphylactic reaction may experience:

• swelling of the mouth, lips and tongue
• difficulty swallowing
• difficulty breathing
• wheezing or persistent cough
• feeling lightheaded or faint
• an itchy raised rash
• flushing of the skin
• vomiting and/or diarrhoea
• sense of impending doom (feeling something bad will happen)
• feeling dizzy (low blood pressure)
• loss of consciousness.

Reactions can present in two different ways:

1. Uniphasic – Where symptoms occur rapidly but respond to treatment and there is a full recovery.
2. Biphasic – Where the reaction responds to treatment and there is a period of time with no symptoms, but symptoms then reoccur.

The possibility of a biphasic reaction means that it is important to seek medical advice following an anaphylactic reaction.

Treatment for anaphylaxis

Those people known to be at risk of anaphylaxis should identify the risk factors and avoid the triggers where possible.

Children and adults may get warning signs of an allergic reaction and therefore have medication to use to help prevent a full anaphylactic reaction e.g antihistamine and/or inhalers.

The only treatment for an anaphylactic reaction is adrenaline; people known to be at risk of anaphylaxis will be prescribed an auto-injector device containing this.  The most commonly prescribed devices in the UK are Epipen, Jext and Emerade.

Anaphylaxis training course

This information was taken from our Anaphylaxis training course that has been endorsed by The School and Public Health Nurses Association (SAPHNA).

The course is available to buy online or can be added to our online learning service as part of our Health Awareness package alongside courses on Asthma, Diabetes and Epilepsy.

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