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Quick guide · 3 min read
Anaphylaxis: Severe Allergic Reaction
A severe allergic reaction can close the airway in minutes. Use their adrenaline auto-injector (EpiPen or similar) into the outer thigh immediately, call 999 and say the word anaphylaxis, and lie them flat with legs raised. A second dose can be given after five minutes if they are not improving.
Spot it
- Swelling of the face, lips or tongue; tightening throat; hoarse voice
- Wheeze or serious difficulty breathing
- Widespread hives or flushing, often with a known trigger: food, a sting, a medicine
- Dizziness, collapse, a feeling of dread
What to do
- 1
Adrenaline first, without delay.
Their auto-injector (EpiPen, Jext) into the outer thigh, through clothing if needed. Hold as the device instructs. Adrenaline is the treatment; antihistamines are not enough for anaphylaxis.
- 2
Call 999 and say "anaphylaxis".
That word changes the response. Ambulance always, even if they improve: reactions can rebound hours later.
- 3
Position them.
Lie them flat and raise the legs. Struggling to breathe? Let them sit up slightly. Pregnant: on the left side. Never let them stand or walk suddenly, it can cause fatal collapse.
- 4
No improvement after 5 minutes: second injector.
Many people carry two. If they become unresponsive and stop breathing normally, start CPR.
Do
- Inject adrenaline early, into the outer thigh
- Say the word anaphylaxis on the 999 call
- Keep them lying down, legs raised
Don't
- Do not wait to see if it gets better on its own
- Do not stand them up or walk them, even if they feel recovered
- Do not rely on antihistamines in a severe reaction
Common questions
Where does an EpiPen go?
Into the muscle of the outer thigh, through clothing if necessary. Follow the device's instructions, hold it in place as directed, then call 999 and say anaphylaxis. A second dose can be given after five minutes if there is no improvement.
Do they still need hospital if the EpiPen worked?
Yes, always. Anaphylaxis can return hours after the first reaction (a biphasic reaction), so they need observation even when they feel fine.
Related skills
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