How to Recognize a Stroke: FAST Signs Everyone Should Know

Stroke symptoms don't announce themselves. They show up mid-sentence, mid-step, mid-meal — and the person having them is often the last to notice something is wrong. That's why FAST exists: a four-part check a bystander, a spouse, or a coworker can run in under 30 seconds, with no medical background required.

The FAST Test

FAST is an acronym developed for exactly one purpose: getting non-medical people to recognize stroke fast enough to matter. Run through it the moment you suspect something is off.

• ›Face: Ask the person to smile. Does one side of the face droop or fail to move?
• ›Arms: Ask them to raise both arms and hold them up. Does one arm drift downward or fail to lift?
• ›Speech: Ask them to repeat a simple sentence. Is the speech slurred, strange, or hard to produce?
• ›Time: If any of the above are present, call 911 immediately. Note the time symptoms started — you will be asked.

A single positive finding — even one that seems mild or that resolves before the ambulance arrives — is enough to call. Do not wait to see if it happens again or gets worse.

Signs FAST Doesn't Capture

FAST is deliberately simple, which means it misses some stroke presentations. Many hospitals now teach an expanded version, BE-FAST, adding two more checks:

• ›Balance: Sudden loss of balance or coordination, or an inability to walk a straight line
• ›Eyes: Sudden vision loss, double vision, or blurred vision in one or both eyes

Two additional symptoms deserve the same urgency even though they don't fit either acronym: a sudden, severe headache unlike any before it, and sudden confusion or difficulty understanding speech (even without slurring). Any of these, appearing suddenly, warrants the same response as a positive FAST check — call 911.

What to Do in the First Minutes

What you do — or don't do — before the ambulance arrives matters. A few rules:

• ›Call 911. Do not drive the person to the hospital yourself — EMS can begin stroke protocols en route and alert the receiving hospital before arrival.
• ›Note the exact time symptoms began, or the last time the person was known to be normal. This single detail determines which treatments they qualify for.
• ›Do not give food, water, or medication. Stroke can affect swallowing, and aspiration is a real risk.
• ›Keep the person safe and still. Lay them on their side if they are vomiting or losing consciousness.

Why Every Minute Counts

During an ischemic stroke, the brain loses an estimated 1.9 million neurons per minute of untreated blockage. Clot-dissolving medication (tPA) has a treatment window of roughly 3 to 4.5 hours from symptom onset. Mechanical clot retrieval can extend that window further in select cases — but every option narrows with time, and some close completely. This is the entire reason FAST exists: not to diagnose, but to compress the time between "something's wrong" and "help is coming."

Reducing Your Risk Before It Happens

Recognizing symptoms is damage control. The better position is knowing your risk before a stroke or TIA ever occurs. Roughly 1 in 5 ischemic strokes trace back to carotid artery disease — plaque buildup in the neck arteries that supply the brain, which develops silently for years with no symptoms at all. A carotid duplex ultrasound images those arteries directly and finds narrowing before it causes an event, not after.

If you have high cholesterol, hypertension, diabetes, a smoking history, or a family history of stroke, that screening is worth having on record — not as an emergency measure, but as a baseline.