What is anaphylaxis?
Anaphylaxis is a severe, potentially life-threatening allergic reaction. It affects the whole body, often within minutes of exposure to the allergen (the substance which causes the allergic reaction) but symptoms can sometimes start hours later.
What happens when you have an anaphylactic reaction?
Anaphylactic shock, like all allergic reactions, occurs because the body’s immune system reacts inappropriately in response to the presence of a substance that it wrongly perceives as a threat.
To fight the “threat”, the immune system releases a flood of chemical substances, including histamine, from cells in the blood and tissues where they are stored. The released chemicals act on blood vessels to cause swelling. In people with asthma, the effect is mainly on the lungs and there may also be a dramatic fall in blood pressure. When this happens major organs don’t get the blood and oxygen they need to function, and your body goes into anaphylactic shock.
Signs and symptoms – what are the first signs of anaphylaxis?
- Blotchy skin rash or flushing
- Swelling of the tongue and/or throat
- Difficulty in swallowing or speaking
- Vocal changes (hoarse voice)
- Wheeze or persistent cough or severe asthma
- Difficult or noisy breathing
- Stomach cramps or vomiting after an insect sting
- Dizziness / collapse / loss of consciousness
- Sense of impending doom
You will not necessarily experience all of the signs and symptoms listed above and there are several different types of reaction which could occur:
• Uniphasic – these come on quickly and symptoms get rapidly worse, but once treated, the symptoms go and don’t return.
• Bi-phasic – these are reactions which may be mild or severe to start with, followed by a period of time when there are no symptoms, and then increasing symptoms with breathing and blood-pressure problems.
What causes anaphylaxis?
Some of the most common allergens include:
grass and tree pollen (hay fever)
animal dander (tiny flakes of skin or hair)
food allergy (particularly fruits, seafood and nuts)
medicines (including antibiotics such as penicillin)
In some people, exercise can trigger a severe reaction — either on its own or in combination with other factors such as food or drugs (such as aspirin)
What is the treatment for anaphylaxis?
The emergency treatment for anaphylaxis is adrenaline, also known as epinephrine – that’s where the Epi in Epi-pen comes from.
Adrenaline acts quickly to constrict blood vessels, relax smooth muscles in the lungs to improve breathing, stimulate the heartbeat and help to stop swelling around the face and lips.
If you are at risk of anaphylaxis, your doctor will prescribe adrenaline in the form of a pre-loaded adrenaline auto injector (AAI) The 3 main AAI’s currently available are Epi-pen, Jext and Emerade.
You should carry 2 of these with you at all times.
First Aid for Anaphylaxis
Remember to stay as calm as possible so that you can reassure the casualty:
- Call 999 OR 112 for an ambulance
- Check whether the casualty is carrying an adrenaline auto-injector (AAI). Assist them to use it, if necessary
- If the casualty is unable to administer the medication themselves you can administer it to them
- The casualty should be lying down and remain as still as possible
- Raise their legs if they feel dizzy or faint or appear pale and sweating
- Raise their shoulders if they feel wheezy or short of breath
- If the casualty becomes unconscious, check Airway and Breathing and start CPR if necessary
- If the casualty has more than one auto-injector, the dose of adrenaline can be repeated at 5 minute intervals if there is no improvement
- IMPORTANT: DO NOT sit the casualty up once they are lying down
Book onto a first aid course today to get confident in lifesaving first aid skills!