As fans of the Netflix series Bridgerton will know, anaphylaxis is a severe, potentially life-threatening allergic reaction. It affects the whole body.

What happens when someone has 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, such as an insect sting. 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 and cause swelling.

Which substances can trigger anaphylaxis?

Some of the most common allergens include:

• Foods such as seafood, nuts and cow’s milk
• Medicines (including antibiotics such as penicillin)
• Insect stings and bites
• Latex

In some people, exercise can trigger a severe reaction — either on its own or in combination with other factors (such as food or medicines). 

Does anaphylaxis happen immediately?

It often happens within minutes of exposure to the allergen (the substance which causes the allergic reaction) but symptoms can sometimes start hours later.

How many people experience anaphylaxis?

According to the BMJ, between 1998 and 2018, 101,891 people were admitted to hospital for anaphylaxis. Of these admissions, 30,700 (30.1%) were coded as due to a food trigger.

Can anaphylaxis develop at any age?

Yes. According to the NHS, anaphylaxis is not common, but people of all ages can be affected. People with other allergic conditions, such as asthma or the allergic skin condition atopic eczema, are most at risk of developing anaphylaxis.

Does anaphylaxis always need urgent treatment?

Yes. We’ll explain more later in this blog.

Are children at risk of anaphylaxis?

Unfortunately, there have been fatal incidents at school. According to Anaphylaxis UK, every school class is likely to have at least one pupil with allergies so teachers must understand how to give appropriate first aid. In 2020, the BMJ noted that cow’s milk had become the most common single cause of fatal anaphylaxis in school-aged children.

Is anaphylaxis upsetting to see?

Yes. Even if your first aid training is up to date, witnessing someone with anaphylaxis difficulties can be quite harrowing. It’s normal to feel panicked (although maybe not quite as much as Anthony Bridgerton (!) and we certainly don’t recommend wasting time gazing into the casualty’s eyes). The rest of this blog will help you remember what to do so you can stay calm and let your knowledge kick in.

Signs and symptoms – what are the first signs of anaphylaxis?

Allergy UK lists the following symptoms of anaphylaxis: Airway:

• Swollen tongue
• Difficulty swallowing/speaking
• Throat tightness
• Change in voice (hoarse or croaky sounds)

Breathing:

• Difficult or noisy breathing
• Chest tightness
• Persistent cough
• Wheeze (whistling noise due to a narrowed airway)

Circulation:

• Feeling dizzy or faint
• Collapse
• In babies and young children this may look like the sudden onset of paleness and floppiness
• Loss of consciousness (unresponsive)

A casualty will not necessarily experience all of these. Please note: there may be other signs, such as a bee or wasp caught in clothing.

What is the treatment for anaphylaxis?

The emergency treatment for anaphylaxis is adrenaline, also known as epinephrine. If you are at risk of anaphylaxis, your doctor will prescribe adrenaline in the form of a pre-loaded adrenaline auto-injector (AAI). The two main AAIs currently available are Epi-pen and Jext. Allergy UK advises, “It is recommended that you carry two AAIs at all times, this is particularly important for people who have allergic asthma and a food allergy as they may be at an increased risk of a severe allergic reaction.”

How do AAIs work?

We love this description from the Asthma and Allergy Network: “When epinephrine is injected, it triggers a sudden burst of adrenaline to multiple areas of the body simultaneously. Your heart begins to beat faster and stronger. Your airways open. The blood goes to your vital organs and away from your skin. All of a sudden, you breathe easier. You stop itching and feel less lightheaded, and your pulse stops racing. Epinephrine is so effective, it reverses the life-threatening allergic reaction.”

How do I give first aid to someone experiencing anaphylaxis

Here’s what to do:

• Ensure the casualty lies down and remains as still as possible (important: don’t sit them up once they’re lying down!)
• Raise their legs if they feel dizzy, faint or appear pale and sweating
• Raise their shoulders if they feel wheezy or short of breath
• Check if the casualty is carrying an AAI. Assist them to use it, if necessary
• If the casualty is unable to administer the medication themselves, you can administer it to them*
• Make a note of the time the AAI was administered
• Call 999 OR 112 for an ambulance. Tell the operator that the casualty is experiencing anaphylaxis(ana-fil-axis)
• If the casualty becomes unconscious, check their airway and breathing. Start CPR, if necessary
• If the casualty has more than one AAI, the dose of adrenaline can be repeated at five-minute intervals if there is no improvement

*An AAI should be given into the muscle in the outer thigh. It can be given through clothes if necessary, avoiding bulky pockets or seams. Remember to stay as calm as possible so you sound reassuring. Do you want to feel more confident in your lifesaving first aid skills? Join one of our in-person first aid training courses.