So, what does anaphylaxis look like? and how we should respond when every second counts.
Written by Stephanie Austin, Founder & Lead Trainer, Prima Cura Training
Reviewed & Updated: February 2026 This article reflects current UK guidance from Anaphylaxis UK, Resuscitation Council UK, NHS clinical advice & MHRA approval for Neffy Nasal Spray.
Let’s start with something important.
There isn’t always dramatic gasping. There isn’t always an instant collapse. There isn’t always someone shouting “they’re allergic!”
Sometimes it starts with someone saying they feel a bit strange. Maybe their lips feel tingly. Maybe they say their throat feels tight. Maybe they look anxious in a way that doesn’t quite fit the situation.
And that’s where people hesitate.
Because they’re not sure yet.
The problem is, anaphylaxis doesn’t wait for certainty.
According to Anaphylaxis UK, around 1–2% of the UK population is estimated to be at risk of anaphylaxis. Hospital admissions have risen significantly over the past two decades, particularly in children and young people.
That means this isn’t rare.
If you work in:
You are likely to encounter someone with a serious allergy at some point.
This isn’t niche knowledge anymore. It’s mainstream safety.
Anaphylaxis is a severe, life-threatening allergic reaction that affects multiple systems in the body. It happens when the immune system overreacts to something it sees as a threat, releasing chemicals that cause:
The real danger is not the rash.
The real danger is airway compromise and circulatory collapse.
That’s why early adrenaline matters.
Guidance from the Resuscitation Council UK and the NHS is clear on this.
Common triggers include:
Food is the most common cause in children. Medication and insect stings are more common in adults. It is important to remember that anyone can be allergic to just about anything!
Sometimes the person knows they’re allergic and carries adrenaline.
Sometimes this is their first severe reaction.
That unpredictability is why awareness matters so much.
It can affect several systems at once. Recognising the pattern is more important than memorising a checklist.
Airway Symptoms (This Is Serious)
If someone says, “My throat feels tight,” treat that as a red flag. Do not wait for it to get worse.
Breathing Changes
Breathing difficulty is an emergency. Full stop.
Circulation Problems
If someone suddenly looks grey, sweaty and faint after allergen exposure, that is not minor.
Skin and Gut Symptoms
Important: a rash may be present, but it might not be. The absence of a rash does not rule out anaphylaxis.
That misunderstanding causes dangerous delays.
Often within minutes.
Sometimes within seconds.
Occasionally, it may appear mild at first and then suddenly worsen.
There is also something called biphasic anaphylaxis, where symptoms return hours later. That’s why ambulance attendance is always required, even if adrenaline appears to work.
Do not “watch and wait”.
Current guidance from the Resuscitation Council UK and the NHS is very clear:
Adrenaline is the first-line treatment.
Not antihistamines.
Not water.
Not waiting to see if it improves.
Adrenaline.
Common devices include:
They are injected into the outer thigh, through clothing if necessary.
If there is no improvement after 5 minutes and a second injector is available, it can be used.
Adrenaline is extremely safe when used appropriately in suspected anaphylaxis. Delaying it is far more dangerous than giving it.
Anaphylaxis UK have a handy video on autoinjectors, which you can find here.
You may have seen news coverage about Neffy, the needle-free adrenaline nasal spray.
As of 2026, Neffy has received regulatory approval for use in the UK. That’s a significant development, particularly for individuals who are needle-averse or anxious about injections.
However (and this is important), UK emergency guidance still centres on rapid administration of adrenaline as the first-line treatment for anaphylaxis. Whether delivered via:
The key principle remains exactly the same:
Adrenaline must be given promptly at the first signs of serious reaction.
At present, auto-injectors remain the most widely prescribed and commonly available emergency treatment in UK workplaces, schools and public settings. Nasal adrenaline may become more common over time, depending on prescribing practice and updated clinical guidance.
As always, first aiders should:
Training evolves as guidance evolves. What does not change is the priority: early adrenaline saves lives.
For the most up-to-date clinical recommendations, refer to Resuscitation Council UK, Anaphylaxis UK, and the NHS.
For nursing and care settings, refer to NICE Quality Standard Reference number QS119
Higher risk groups include:
Asthma combined with allergy increases the risk significantly.
If you are responsible for a school, nursery, care setting or food environment, your risk assessment should reflect that.
Under UK law, employers must provide suitable and sufficient first aid arrangements. The Health and Safety Executive makes that very clear.
If allergens are part of your environment, awareness training matters.
I’ve taught thousands of learners across the UK, and the biggest barrier in real emergencies isn’t a lack of compassion. It’s hesitation.
People second-guess themselves.
They wait for it to become “obvious”.
They worry about overreacting.
In anaphylaxis, hesitation is the risk.
When people understand what they’re looking for, they act faster. When they’ve practised using trainers, they are calmer. When they understand why adrenaline is a first-line treatment, they don’t delay.
That’s why proper First Aid at Work training and Anaphylaxis Awareness training matter.
This isn’t about ticking compliance boxes. It’s about real-world confidence.
If you are responsible for staff or service users, ask yourself:
First aid provision should reflect real risks, not just minimum standards.
Anaphylaxis can be subtle at first.
It can escalate quickly.
It can happen in a classroom, a restaurant, a care home, a workplace kitchen, or during a team lunch.
But it follows patterns.
Airway.
Breathing.
Circulation.
If those are compromised after suspected allergen exposure, act.
Call 999.
Use adrenaline.
Keep them safe until help arrives.
Confidence comes from understanding what you’re seeing. And that understanding comes from proper training, not guesswork.
Disclaimer: This article is for general information only and reflects UK guidance at the time of review (February 2026). It does not replace professional medical advice, diagnosis or emergency care. In suspected anaphylaxis, call 999 immediately and follow current UK guidance from the Resuscitation Council UK and the NHS. Always use prescribed adrenaline auto-injectors as directed. Employers must ensure their first aid arrangements comply with current Health and Safety Executive requirements and reflect their organisational risk assessment.
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