Emergency medicine
Adrenaline (Epinephrine)
Auto-injector or injection
Quick Summary
Adrenaline quickly reverses swelling of the airway, low blood pressure and wheezing.
Anaphylaxis
Cardiac arrest
Medical Uses
Anaphylaxis: First-line emergency treatment.
Cardiac arrest: Given by medical teams.
How it's taken
An auto-injector is pressed firmly into the outer thigh, through clothing if needed. Then call 112.
Your doctor decides the right dose for you and how long to take it.
Your doctor decides the right dose for you. Follow their instructions and the label.
Common Side Effects
Fast heartbeat
Common and expected.
Shaking
And anxiety.
Headache
Sometimes.
Interactions
Beta blockers
Can reduce effect.
Critical Warnings
Always call 112
Black Box Warning: Even if symptoms improve.
Carry two
People at risk should carry two auto-injectors and check expiry dates.
Sources and further reading
Last updated 21 October 2026. For more detail, see these trusted health organisations.
- Epinephrine Injection: drug information(opens in a new tab) · MedlinePlus, US National Library of Medicine