United Kingdom: Emergency Guidance

If you or someone else may be having a heart attack in the UK, act quickly:

• Call 999 immediately and ask for an ambulance. Do not drive yourself or the person to hospital.
• Keep the person calm and seated comfortably. Loosen any tight clothing and reassure them help is on the way.
• The emergency operator may advise giving one adult‑dose aspirin (300 mg) to chew. Only do this if the person is 16 or older, not allergic to aspirin and has no history of bleeding problems. Do not give aspirin if they are taking anticoagulants or have been told not to take it.
• If the person has prescribed angina medication (such as glyceryl trinitrate spray), assist them in using it.
• Stay with the person. If they become unresponsive and are not breathing normally, begin CPR and use an AED if available.

For detailed national guidance, consult the NHS heart attack information