How to Recognise and Respond to Anaphylaxis

Sometimes, after exposure to an allergen, people experience an allergic reaction. These reactions can vary from mild (such as a small rash) to very severe. The most intense type of allergic reaction is called anaphylaxis. It is important to know how to recognise and respond to the signs of anaphylaxis because it is a serious condition that requires immediate treatment.

What is Anaphylaxis?

Anaphylaxis is a severe type of allergic reaction. The symptoms of anaphylaxis show up quickly after coming into contact with an allergen such as:

• Food
• Insect bite/sting
• Medicine

Allergic reactions, including anaphylaxis, happen due to a problem with the immune system. Our immune system looks after our bodies by reacting to bacteria, infections or other illnesses. An allergic reaction happens when our body mistakes a benign substance for an invader and releases chemicals, including histamine, to attack what it perceives as a threat. 

Knowing how to recognise and respond to an incident of anaphylaxis is an important life-saving skill to have. Additionally, it is especially important for people who work in certain industries, or with at-risk populations, to be allergen aware and able to act quickly if an incident occurs. This includes jobs such as:

• Teachers and support staff in schools or nurseries
• Childminders
• Anyone working in food service or preparation (including chefs, factory workers and servers)
• People in the health and social care sector

If you work with food, you are required by law to display the 14 allergens, either via an allergy sheet, on menus or printed on food labels. Staff who work with food should also undertake relevant training in allergy awareness, which should minimally cover:

• What the 14 allergens are
• What an allergic reaction is
• How to avoid cross-contact/cross-contamination
• Food law and legislation

As part of first aid training, it is also important to cover how to respond if an allergen incident occurs and someone has a reaction, such as staying calm, calling 999 immediately if someone is suffering anaphylaxis and how to use an EpiPen to relieve symptoms (we will cover this in more detail later in the article).

Recognising Anaphylaxis Symptoms

Anaphylaxis can be fatal if not treated promptly, therefore it is important that we know how to recognise the signs and symptoms of this type of allergic reaction. Anaphylaxis is characterised by problems with the airway, breathing or circulation (A,B,C) and often involves changes to the skin (such as a change of colour or the presence of a rash). 

Common symptoms of anaphylaxis include:

• Swollen throat and/or tongue
• Breathing problems (including wheezing, coughing or gasping for air)
• Rapid breathing
• Problems swallowing
• Hoarse voice
• Tiredness and confusion
• Dizziness or feeling faint
• Skin that feels cold to the touch
• Blue, grey or pale skin, lips or tongue

People who have experienced anaphylaxis often report feeling tightness in their throat or like their throat is closing up which often leads them to clutch at their throat area. Some people may also get a rash that is swollen, raised or itchy.

Triggers and Risk Factors

People experience anaphylaxis due to a variety of factors and although anyone is at risk, some people are more prone to severe allergic reactions than others.

Common foods that trigger anaphylaxis include:

• Nuts (including peanuts and tree nuts)
• Cow’s milk
• Eggs
• Fish/shellfish
• Sesame seeds

Some other foods that are associated with anaphylaxis include:

• Fruit
• Soy
• Wheat

Sometimes anaphylaxis can also be brought on by exercise. 

People can also have a severe allergic reaction after an insect bite or sting such as:

• Bee sting
• Wasp sting

People can also experience anaphylaxis after taking medicine or having medical interventions such as:

• Non-steroidal anti-inflammatory drugs NSAIDs
• Anaesthetic
• Antibiotics
• Opiates
• Insulin

An allergy to latex has also been known to trigger an anaphylactic reaction.

Occasionally, the trigger for an allergic reaction is unknown.

You may be at a higher risk of experiencing anaphylaxis if you have asthma, eczema or a family history of allergies.

Estimates suggest that around 1 in every 1,333 people in England has experienced anaphylaxis at some point in their lives. Triggers and risk factors for anaphylaxis are thought to vary with age:

• Food is a common trigger in children
• Severe respiratory reactions are more common in young children due to their relatively narrow airways
• Medicinal triggers are more common in older people
• Insect venom is the most common trigger among middle-aged people

The Importance of Quick Action

An anaphylactic reaction is a medical emergency. Anaphylaxis can come on quickly and the symptoms can progress rapidly. It is vital that help is given as soon as possible to reduce the chances of serious consequences, including death.

Incidents of anaphylaxis and prescriptions for adrenaline auto-injectors are rising; however, thanks to increased understanding of the condition and access to treatment, deaths from anaphylaxis are decreasing. Unfortunately, according to the NHS there are still 20 to 30 deaths each year due to anaphylaxis.

Steps to Respond to Anaphylaxis

The onset of anaphylaxis can be rapid and alarming to witness. If you are present when someone experiences anaphylaxis, try to remain calm as panicking will make the situation worse. As with most emergency situations, you should remember to check A, B, C:

• Airway
• Breathing
• Circulation

Initial treatment for anaphylaxis includes:

• Use an adrenaline auto-injector (EpiPen).
• Call an ambulance by dialling 999 and explain to the dispatcher that someone is having an anaphylactic reaction.
• The patient should lie down with legs raised (if this worsens breathing sit up slowly and rest – do not get up and walk around even if you start to feel better).
• If the reaction is the result of an insect sting, check if the stinger is still lodged in the skin and if so, carefully remove it.
• Wait five minutes and if symptoms are not improving use a second adrenaline auto-injector, if possible.
• Wait for paramedics to arrive to take the patient to hospital. Anyone experiencing anaphylaxis should not be left alone.

Anaphylaxis should always be treated in hospital. Clinical staff will document your symptoms and will need to know what the circumstances were that preceded the reaction to try to isolate a trigger. They will also want to note the time of the onset of the symptoms. 

Hospital treatments may include:

• Adrenaline (given via injection or drip)
• Oxygen
• Intravenous fluids

When you are in hospital you will be monitored and have some readings taken, which may include your:

• Pulse
• ECG
• Blood pressure
• Blood test

Adrenaline given as an intra-muscular (IM) injection is always the first line of treatment for anaphylaxis. The correct dosage is usually calculated based on a patient’s age:

• Adults 500 micrograms IM (0.5ml)
• Children over 12 years of age 500 micrograms IM (0.5ml)
• Children 6-12 years of age 300 micrograms IM (0.3 ml)
• Children less than 6 years of age 150 micrograms IM (0.15ml)

After anaphylaxis, you will usually be prescribed an adrenaline auto-injector to take home with you. This device will contain the correct dosage of adrenaline based on your age. 

Outcomes are better for people experiencing anaphylaxis if they are not alone when the attack happens, they have their EpiPen or similar device to hand and appropriate treatment is sought quickly.

Aftermath and Follow-up

After an anaphylactic reaction, you will be treated in hospital and monitored for a period of time. In rare cases (less than 9% of adults), a second wave of symptoms can develop, known as a biphasic reaction. Hospital staff will want to monitor you to check that you are recovering properly and will need to give you information about follow-up treatment and how to live with anaphylaxis. 

If it is unknown what caused the incident, you may be referred for allergy testing to find the trigger. Referral pathways for allergy testing vary between children and adults. You will also be given two small devices that contain adrenaline, known as adrenaline auto-injectors, that you need to keep with you. 

Additional advice for people who have had anaphylaxis includes:

• Learn to recognise the symptoms of anaphylaxis and how to respond
• Make sure people know about your allergy and potential reaction, including friends, family, teachers etc
• If your reaction involved exercise, make sure you take some safeguarding measures (for example not exercising alone or in isolated areas, taking your mobile phone with you, resting at the first sign of a reaction)
• Carry your TWO adrenaline auto-injectors with you all the times
• Check that your adrenaline auto-injectors are in date and replace as required (some brands offer a text alert service to let you know when your device needs replacing)
• Know how to use your adrenaline auto-injector and use it at the first signs that you are having an allergic reaction rather than waiting for symptoms to progress
• Adrenaline is sensitive to temperature and should not be stored above 25 degrees centigrade or put in the fridge
• Ask your doctor if you have questions or concerns, such as extra precautions you need to take when travelling

Additionally, before leaving hospital patients will benefit from being given information about any referrals or follow-ups they will need (such as allergy testing) and any patient support groups that are available. 

Once you have an idea what it is you are allergic to, you will need to avoid triggers as far as possible. If you have a food allergy, make sure you check food labels carefully for allergens. If you have a severe allergy, you should also pay attention to precautionary labelling; this may look like ‘May contain X’ or ‘Produced in a factory that also handles X’. Changes in food law and the wide availability of ‘free from’ and allergy friendly alternatives are thankfully making life easier for people who live with severe food allergies. 

Some people with severe allergies may be suitable candidates for immunotherapy. This is where patients are gradually exposed to increasing amounts of something they are allergic to over a period of time (sometimes up to 5 years). Venom immunotherapy is especially effective, giving 98% protection against wasp venom reactions and around 90% protection against bee stings. Around 10% of patients experience reactions to the immunotherapy itself and it is best discussed with an allergy specialist before deciding to go down this route. 

Other triggers are more difficult to control, such as environmental factors or allergies to pollen or insect stings. In such cases, it is vital that anyone who has experienced anaphylaxis has access to adrenaline and knows what to do in the event of an emergency. It is critical that you (and those around you) know how to locate and use the auto-injector in the event of an anaphylactic reaction. You can order a ‘trainer’ pen to practise with; trainer pens are empty and do not have the sharp point that real auto-injectors have. 

There are different types of adrenaline auto-injectors on the market. The most common is an EpiPen. Instructions are printed on the side of the device and can also be found on the website for the brand that you have been given.

Generally, they are straight forward and simple to use:

• Remove the safety cap from the injector 
• Hold it 10cm away from the skin then jab it firmly into the thigh at a right angle
• A ‘click’ sound means that adrenaline release has been activated 
• Keep it in place for 10 seconds
• Make sure the patient is lying down and does not get up or walk around, even if their symptoms start to improve
• Use a second adrenaline shot if no improvement is made within 5 minutes 

An auto-injector can be used in the thigh area through clothing, providing that the needle is able to penetrate the skin.

Anaphylaxis is an extreme type of allergic reaction that should always be treated as a medical emergency. Being able to recognise and respond to anaphylaxis is an important skill to have, one that could potentially save someone’s life. When someone is in medical peril, remember to check A, B, C (airway, breathing, circulation). If you see someone experiencing anaphylaxis, you can help them by administering adrenaline using their auto-injector (if they have one), calling an ambulance immediately and waiting with them until paramedics arrive.