Emergency

Heart Attack

If you suspect a heart attack, call 999 immediately, help the person sit down and rest, and give them aspirin to chew if they are not allergic.

When to call 999. Call 999 immediately for chest pain or tightness that lasts more than a few minutes or spreads to the arm, jaw, neck or back, especially with breathlessness, sweating, nausea or a feeling of dread. Do not wait to see if it passes.

Written by Meds Global Health Clinical Team · Clinically reviewed by Dr Muhammad Suffyan, MB BS, Founder & Clinical Director · Last reviewed · How we review

What to do

  1. Call 999 straight away and say you think someone is having a heart attack.
  2. Help the person sit down and rest — a semi-sitting position, leaning back with knees bent, is often most comfortable.
  3. Keep them calm and reassured, and loosen any tight clothing.
  4. If they are not allergic to aspirin and it is available, give them a single adult aspirin (300 mg) to chew slowly.
  5. If they have their own medicine for angina (such as a GTN spray), help them use it.
  6. Stay with them and monitor closely. If they become unresponsive and stop breathing normally, start CPR.

Avoid

What not to do

Do not let the person drive themselves to hospital or delay calling 999. Do not give aspirin if they are allergic to it or have been told not to take it. Do not give food or drink other than the aspirin.

Afterwards and while you wait

Keep the person resting and calm while waiting, and be ready to start CPR if they collapse. Tell the ambulance crew what time symptoms started, what medicines were given, and any known heart problems or allergies.

Education and reference only. This is general first-aid information aligned with UK guidance, not a substitute for a hands-on first-aid course or professional emergency care. In a life-threatening emergency, call 999 straight away.

Answers

Heart Attack: frequently asked questions

Why give aspirin during a heart attack?

Chewing a single 300 mg aspirin helps thin the blood and can limit the damage during a heart attack. Only give it if the person is not allergic and it is readily available — do not go hunting for it or delay calling 999.

What if I am not sure it is a heart attack?

Call 999 anyway. It is safer to be checked than to wait. Paramedics can quickly assess the heart, and early treatment saves heart muscle and lives.

Related

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Sources

Where this is drawn from

  • NHS — first aid
  • Resuscitation Council UK
  • St John Ambulance / British Red Cross first-aid guidance

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