Stroke signs and what to do in the first minutes

A stroke happens when blood stops flowing to part of the brain. The NHS teaches the word FAST: face, arms, speech and time to call for help. In practice that means checking whether one side of the face has dropped or the smile is uneven, whether one arm drifts downward or feels weak or numb when both are raised, and whether speech is slurred or hard to understand.

The American Stroke Association (ASA) has extended this to B.E. F.A.S.T., adding balance loss and eye or vision changes. Other sudden signs the NHS and ASA list include confusion, trouble speaking or understanding speech, dizziness or falling, and a severe headache with no known cause. The ASA notes that some signs in women, such as general weakness, confusion, fatigue, nausea or vomiting, can be subtle enough to be brushed off. The key word in every list is sudden.

Call your local emergency number straight away. Numbers differ by country: the NHS gives 999 for the United Kingdom, and the ASA and the US Centers for Disease Control and Prevention (CDC) give 911 for the United States. The NHS says plainly not to drive yourself to hospital, and the CDC advises against driving or being driven privately, because calling an ambulance means treatment can start on the way.

Note the time the symptoms first appeared and tell the call handler and the hospital team. The CDC says providers use that time to choose treatment, and adds that the most effective stroke treatments are generally available only within 3 hours of the first symptoms. The World Health Organization (WHO) states that a suspected stroke should be treated as a health emergency, and that clot-busting therapy should be given as soon as possible, within hours of symptom onset. The ASA puts it this way: early treatment leads to higher survival rates and lower disability rates.

A brief episode is no reason to wait. A transient ischaemic attack (TIA, or "mini-stroke") has the same symptoms but clears. The ASA says to call for help even if the symptoms go away, and the NHS says anyone who has had stroke signs in the last 24 hours should call, even if they have stopped. See atrial fibrillation, stroke and the heart-brain link for why a TIA is treated as a warning.

The WHO describes an ischaemic stroke as one in which a blood clot blocks a blood vessel in the brain, cutting off blood flow. A haemorrhagic stroke happens when a blood vessel in the brain ruptures and bleeds. Scans such as CT or MRI help doctors tell them apart, which matters because treatment depends on the type.

One route to an ischaemic stroke begins in the heart. The irregular rhythm called atrial fibrillation can allow clots to form in the heart and travel to the brain. The NHS lists atrial fibrillation among conditions that increase stroke risk.

The WHO calls hypertension the leading contributor to stroke and says people with hypertension have a nearly three times higher risk of stroke. High blood pressure often causes no symptoms, so checking it matters; measuring blood pressure at home explains how. The NHS also lists diabetes, high cholesterol, atrial fibrillation, previous TIA, an unhealthy lifestyle, sickle cell disease and age over 50 among risks, and says risk is higher for people from a Black or South Asian background.

For sub-Saharan Africa, a review in Nature Reviews Neurology by African and international authors reports that hypertension remains the most important modifiable risk factor for stroke in Africa. The same review says the numbers of stroke rehabilitation professionals appear insufficient and that studies of rehabilitation in African stroke units are scarce. Local access to care varies, which is one more reason to know the signs.

Recovery depends on how much the stroke has affected a person. The NHS says some people recover within days or weeks, while others need months or years. Rehabilitation, which the WHO says should begin as soon as the person is medically stable, can include physiotherapy, exercises for speech, swallowing and vision, support for memory and mood, and equipment for home. The NHS says a review of progress should happen after about 6 months. Family and carers often take a large part, and they are encouraged to seek support too.

Call the local emergency number immediately for any sudden face, arm, speech, balance, vision or severe headache symptoms, even if they pass. Do not wait to see whether they settle, and do not drive yourself. For high blood pressure, diabetes or an irregular pulse, see a clinician who can check and treat these before a stroke happens.

Stroke signs come on suddenly, and FAST (with balance and vision added by the ASA) is a quick way to spot them. Call the local emergency number at once, note when symptoms began and do not drive. High blood pressure is the biggest risk factor, and rehabilitation starts early and continues for as long as the person needs.