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Plain-language information for patients

What is a stroke?

A stroke is a 'brain attack' — it happens when the blood supply to part of the brain is cut off, either by a clot (ischaemic stroke) or a bleed (haemorrhagic stroke). Brain cells start to die quickly, so treatment is urgent.

Act FAST — call 999

Use the FAST test: Face — has it dropped on one side, can they smile? Arms — can they raise both and keep them up? Speech — is it slurred or muddled? Time — if you see any of these signs, call 999 immediately.

Other sudden symptoms include numbness or weakness down one side, sudden visual loss, severe headache, or difficulty understanding speech. Note the time symptoms started — it affects treatment.

Why speed matters

For a clot-type stroke, treatments that remove or dissolve the clot work best within the first few hours, so getting to a specialist stroke unit fast can dramatically improve recovery.

A transient ischaemic attack (TIA, or 'mini-stroke') causes the same symptoms but they pass — it is still an emergency and a warning sign, and needs urgent assessment.

Common questions

What is the difference between a stroke and a TIA?

A TIA has the same symptoms but they resolve, usually within minutes to an hour, because the blockage is temporary. It is a warning of possible future stroke and needs urgent specialist review.

Related tools

These calculators are designed for healthcare professionals.

This page is general information, not personal medical advice, and does not replace a consultation with a qualified health professional. If you are worried about your health, please speak to your GP, pharmacist, or another clinician. Last reviewed 2026-06-09.