Allergy

How to Recognize Anaphylaxis and Use an Adrenaline Auto-Injector

A patient-friendly guide to the warning signs of anaphylaxis, when to use adrenaline, and what to do next.

Patient information page | Last reviewed: June 2026

Emergency action

If anaphylaxis is suspected, use the adrenaline auto-injector immediately and call emergency services. Say clearly: “anaphylaxis.”

Printable resource: Keep a copy of the action plan with medicines, school forms, travel documents, or care instructions.

Download the printable action plan

What is anaphylaxis?

Anaphylaxis is a serious allergic reaction that can develop quickly. It is most concerning when allergy symptoms affect the airway, breathing, or circulation. Food, insect stings, medicines, and latex are common triggers, but sometimes the trigger is not obvious at the time.

Recognizing the symptoms

If airway, breathing, or circulation symptoms are present after a likely allergen exposure, treat it as an emergency.

Airway

Swollen tongue or throat, tight throat, difficulty swallowing, or a hoarse voice.

Breathing

Wheeze, persistent cough, noisy breathing, or shortness of breath.

Circulation or brain

Dizziness, faintness, collapse, pale or floppy child, confusion, or severe drowsiness.

Skin symptoms such as hives, itching, or swelling are common, but anaphylaxis can occur even if the skin looks normal.

The emergency sequence

  1. Use the adrenaline auto-injector immediately if anaphylaxis is suspected. Adrenaline is the first-line emergency treatment. Antihistamines and inhalers may have a role in some reactions, but they are not a substitute for adrenaline.

  2. Call emergency services and say “anaphylaxis”. If another person is present, ask them to call while the injection is given.

  3. Position correctly. Lay the person flat with legs raised if possible. Do not let them stand or walk. If breathing is difficult, allow them to sit with legs outstretched.

  4. Use a second auto-injector after 5 minutes if symptoms have not improved or are getting worse.

  5. Start CPR if there are no signs of life and follow emergency operator instructions.

Where does the injection go?

Correct site

Adrenaline auto-injectors are usually given into the outer mid-thigh. They can generally be used through clothing if needed.

Avoid these sites

Do not inject into hands, feet, buttocks, or a vein. Hold a young child’s leg still to reduce movement during the injection.

Brand-specific reminders

Always follow the instructions supplied with the prescribed brand. The instructions below are a reminder, not a replacement for device training. If the prescribed brand is different, use that brand’s own instructions. Ask a pharmacist, doctor, allergy clinic, or school nurse for a trainer device demonstration.

EpiPen

Remove the blue safety cap. Place the orange tip to the outer thigh. Jab firmly at a right angle until activated. Hold firmly for 3 seconds, then remove. Call emergency services and say anaphylaxis.

Jext

Remove the yellow cap. Place the black tip to the outer thigh at a right angle. Push firmly until it clicks. Hold for 10 seconds, then remove. Call emergency services and say anaphylaxis.

Why carry two devices?

People at risk of anaphylaxis are usually advised to have two in-date adrenaline auto-injectors available. The second device matters because a first dose may not be enough, symptoms may continue, or a device may misfire or be used incorrectly during panic.

Common mistakes to avoid

  • Keeping the device in a bag that is not nearby.
  • Letting devices expire without replacing them.
  • Waiting for a rash before treating breathing or collapse symptoms.
  • Trying to drive to the hospital instead of calling emergency services.
  • Standing or walking after adrenaline because the person feels better.
  • Using antihistamines first in a severe reaction and delaying adrenaline.

After the injection

The person still needs urgent medical assessment even if they improve. Symptoms can return, and observation may be needed. Keep the used device to show ambulance staff if safe to do so. Replace used or expired devices promptly.

Written by: Dr Ranjeetha Shenoy, MBBS, MS (Surgery), DNB (Thoracic Surgery), doctor in primary and hospital care.

Important Notice: The information here is educational and should not replace individual medical advice. Please speak to your own doctor for diagnosis and treatment. If urgent or severe symptoms occur, seek emergency medical help immediately.