What Should You Do Immediately for Anaphylaxis?
Anaphylaxis is a severe, potentially life-threatening allergic reaction. After an insect sting—or another allergy trigger—breathing difficulties, throat swelling or collapse mean you must act fast.
If you think anaphylaxis is happening now: use an adrenaline auto-injector, call 112 in Spain, and lie down. Do not wait for symptoms to get worse.
The four immediate steps
1. Use an adrenaline auto-injector immediately
Adrenaline, also called epinephrine, is the first-line emergency treatment for anaphylaxis. An auto-injector is a device designed to deliver a measured dose quickly.
If one is available:
- Inject it into the outer thigh, following that device’s instructions.
- Follow its directions for removing any safety cap and holding the device in place; these vary between brands.
- Do not wait to see whether the reaction settles by itself.
Adrenaline helps counter the dangerous effects of anaphylaxis, including airway swelling and a sharp fall in blood pressure. Prompt treatment matters because a reaction can worsen quickly.
2. Call emergency services—even if the injection helps
In Spain, call 112 and say clearly:
“I suspect anaphylaxis—a severe allergic reaction.”
Give your exact location, describe the symptoms, and say whether adrenaline has been given and at what time.
If someone else is there, ask them to call while you give the injection. If you are alone, use the injector first, then call; put the phone on speaker if possible so you can follow instructions without moving around.
Call even if you begin to feel better. An initial improvement does not mean the emergency is over. Do not drive yourself to hospital.
3. Lie flat—and do not stand or walk
Your position matters because anaphylaxis can cause blood pressure to fall dangerously.
- Usually: lie flat, with your legs raised if possible.
- If breathing is difficult: gently raise your shoulders or sit up slowly with your legs stretched out. Avoid sudden changes of position.
- If pregnant: lie on your left side.
- If unconscious but breathing normally: someone should place you on your side in the recovery position, which helps keep your airway clear.
Do not stand or walk, even if you feel better after adrenaline. That includes walking to an ambulance or moving to another room.
If someone becomes unresponsive and is not breathing normally, tell the emergency call handler immediately and start CPR—cardiopulmonary resuscitation, which uses chest compressions to help maintain blood flow. Follow the call handler’s instructions.
4. Give a second dose after five minutes if there is no improvement
If symptoms have not improved after five minutes, use a second adrenaline auto-injector if one is available.
Keep track of when each dose was given, and tell the ambulance team. Continue following the emergency call handler’s advice while you wait.
How can you recognise anaphylaxis?
You do not need to identify every possible symptom before taking action. The most concerning signs affect the airway, breathing or circulation—the movement of blood around the body.
| Warning sign | What you might notice |
|---|---|
| Throat or tongue swelling | A swollen tongue, throat tightness or difficulty swallowing |
| Voice changes | A suddenly hoarse voice or difficulty speaking |
| Breathing difficulty | Wheezing, noisy breathing, breathlessness or struggling to breathe |
| Severe dizziness or faintness | Feeling about to pass out, becoming very weak or collapsing |
Anaphylaxis may also cause itching, flushing or hives, which are raised, itchy patches on the skin. However, a rash is not always present. Do not wait for one before responding to serious breathing problems or collapse.
After an insect sting, pain and swelling around the sting site alone do not necessarily mean anaphylaxis. The urgent warning signs are those suggesting a reaction beyond that local area—especially throat swelling, breathing difficulty or severe faintness.
Why an antihistamine is not enough
An antihistamine is a medicine that can help relieve some allergic symptoms, such as itching or hives. It does not replace adrenaline in anaphylaxis.
An antihistamine may ease a rash. It does not reliably treat the airway swelling or dangerous fall in blood pressure that can make anaphylaxis fatal.
Do not take an antihistamine first and wait to see what happens. Do not let searching for tablets, checking the sting site or trying to identify the insect delay adrenaline and the emergency call.
What happens after the immediate danger passes?
You still need emergency medical assessment, even if adrenaline appears to have worked completely. Symptoms can return after initially improving, so hospital observation may be necessary.
After recovery, a clinician can help investigate the trigger, explain whether you need to carry auto-injectors, and provide a written emergency plan. Practising with a trainer device can also make the steps easier to remember under pressure.
For now, the essential sequence is simple:
Adrenaline immediately. Call 112. Lie down—do not walk. Give a second dose after five minutes if there is no improvement.
Sources: NHS guidance on anaphylaxis and Spain’s 112 emergency service.