Stroke Warning Signs: How to Use BE FAST, When to Call 911 and What to Do While You Wait
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Quick answer: the American Stroke Association teaches F.A.S.T.: Face drooping, Arm weakness, Speech difficulty, Time to call 911. Many hospitals add B for balance and E for eyes, making BE FAST. If you see any one of these signs, even if it goes away, call 911 right away, note the time symptoms started, do not let the person drive or go to sleep it off, and do not give aspirin, food or drink unless a dispatcher or doctor tells you to.
Strokes happen in apartments, offices, subway cars and grocery stores, and the person having one is often the last to realize it. Someone nearby who knows the signs can make the call that changes the outcome. The American Stroke Association, a division of the American Heart Association, stresses that stroke is largely treatable when people get emergency care fast.
This guide covers how to spot stroke warning signs, what to do in the first minutes and how to prepare at home. It is part of our apartment emergency kit guide, which covers the supplies and plans every city household should have in place before an emergency.
Sources: American Stroke Association (stroke.org), “Stroke Symptoms” and F.A.S.T. materials; CDC, “Stroke Signs and Symptoms” and “Stroke Facts”; National Institute of Neurological Disorders and Stroke (NINDS), “Stroke”; American Red Cross First Aid guidance. Checked November 2026. This article is general safety information, not medical advice. In an emergency, call 911.
What a Stroke Is and Why Time Matters
A stroke happens when blood flow to part of the brain is blocked or when a blood vessel in the brain bursts. NINDS describes two main types. An ischemic stroke is caused by a blockage, usually a clot, and accounts for most strokes. A hemorrhagic stroke is caused by bleeding in or around the brain.
Brain cells begin to die within minutes when they are deprived of oxygen. Treatments for ischemic stroke, including clot-dissolving medicine and procedures that remove a clot, work best when given early. Hospitals can only offer them after imaging shows which kind of stroke it is. That is the reason every major health organization tells the public to call 911 at the first sign rather than waiting to see whether symptoms improve.
The CDC reports that someone in the United States has a stroke every 40 seconds and that stroke is a leading cause of serious long-term disability. A fast response cannot prevent every stroke, but it can change how much damage one does.
How to Recognize a Stroke: F.A.S.T. and BE FAST
The American Stroke Association uses the F.A.S.T. acronym:
- F, Face drooping: Does one side of the face droop or feel numb? Ask the person to smile. Is the smile uneven?
- A, Arm weakness: Is one arm weak or numb? Ask the person to raise both arms. Does one drift downward?
- S, Speech difficulty: Is speech slurred? Can the person repeat a simple sentence correctly?
- T, Time to call 911: If you see any of these signs, call 911 right away, even if the symptoms go away.
Many hospitals and EMS agencies teach an expanded version called BE FAST, which adds two checks at the start:
- B, Balance: Sudden loss of balance, dizziness or trouble walking
- E, Eyes: Sudden trouble seeing in one or both eyes, or double vision
Other sudden symptoms
The CDC and the American Stroke Association list additional sudden symptoms that can signal a stroke:
- Numbness or weakness of the face, arm or leg, especially on one side of the body
- Confusion, or trouble speaking or understanding speech
- Trouble seeing in one or both eyes
- Trouble walking, dizziness, or loss of balance or coordination
- Severe headache with no known cause
The key word in every list is sudden. A stroke usually comes on abruptly. A person might be fine at breakfast and unable to lift a coffee cup a minute later.
What to Do Right Away
Act in this order.
- Call 911. Say that you think the person is having a stroke. Use the words “possible stroke” so the dispatcher and responders can prepare.
- Note the time. Write down or remember when the symptoms started, or when the person was last known to be normal. Doctors use this to decide which treatments are possible.
- Stay with the person. Keep them as calm and comfortable as you can. If they are sitting or lying down, let them stay there.
- Do not give anything by mouth. Stroke can affect swallowing, and food or drink can cause choking.
- Clear the way for responders. Make sure the apartment door can be opened from outside. In an apartment, send someone to meet the ambulance in the lobby or hold the elevator.
- Gather information. Collect the person’s medication list, any known conditions and their ID if possible.
- Watch breathing. If the person becomes unresponsive and is not breathing normally, start CPR and use an AED if one is available.
Our guide to hands-only CPR and AED basics walks through step 7.
Why an ambulance and not a car
The American Stroke Association recommends calling 911 rather than driving the person to the hospital. Paramedics can begin assessment on the way, alert the hospital so a stroke team is ready, and take the person to a hospital equipped for stroke care. Traffic in a dense city is unpredictable, and a driver focused on the road cannot watch the patient.
The person having symptoms should never drive themselves. Arm weakness and vision changes can make driving dangerous within seconds.
What Not to Do
A few well-meaning actions can cause harm.
Do not give aspirin on your own. Aspirin can help with some heart attacks, but a stroke may be caused by bleeding, and only brain imaging can tell the difference. Let the medical team decide.
Do not let the person sleep it off. Drowsiness or confusion is not a reason to wait. Symptoms that start at night or are found in the morning still call for 911.
Do not wait because symptoms fade. A transient ischemic attack (TIA), sometimes called a mini-stroke, causes stroke-like symptoms that go away. The CDC notes that a TIA is a warning sign of a possible future stroke, and it needs emergency evaluation just like a stroke.
Do not drive them yourself unless 911 is truly unreachable and a dispatcher has advised it.
Do not give food, water or medication. Swallowing problems are common after a stroke.
If You Notice Symptoms in Yourself
Sometimes the person who notices first is the person having the stroke. A sudden inability to lift your arm, a numb face or words that will not come out is frightening, and the instinct is to lie down and wait. The guidance from the American Stroke Association is the same for you as for anyone else: call 911 immediately.
If speaking is hard, stay on the line anyway. Dispatchers are trained to handle callers who cannot talk clearly, and many 911 systems can locate a caller, though location accuracy varies by phone and network. Text-to-911 is available in many areas; the FCC maintains a list of locations that support it, and the standard advice is to call if you can and text only if you cannot.
After calling, take a few practical steps if you are able. Open the apartment door or unbolt it so responders can get in. Sit or lie down somewhere you will not fall, such as the floor near the door. Keep your phone in your hand. If a neighbor, doorman or family member is nearby, call or text them too, but do not let that delay the 911 call.
Setting up your phone’s emergency medical ID ahead of time also helps. Both major phone platforms let you list conditions, medications and emergency contacts that responders can view from the lock screen.
Stroke Risk Factors You Can Talk With a Doctor About
Recognizing a stroke is the emergency skill. Lowering the chance of one is a long-term project for each person and their doctor. The CDC lists several common risk factors:
- High blood pressure, the leading cause of stroke
- High cholesterol
- Heart disease, including atrial fibrillation
- Diabetes
- Smoking
- Obesity and physical inactivity
- A previous stroke or TIA
- Family history and older age
Some risk factors cannot be changed, but many can be managed. Regular blood pressure checks are one of the simplest steps. Many pharmacies have free blood pressure machines, and a doctor can explain what your numbers mean.
Preparing Your Household and Building
Stroke preparation is mostly about information and speed.
Make sure everyone knows the signs
Teach F.A.S.T. or BE FAST to every adult and older child in the home. The acronym is short enough for a refrigerator note. Children as young as school age can learn to call 911 and say “Grandma’s face looks wrong and she can’t talk.”
Keep a medical information sheet
Keep a one-page sheet for each household member listing medications and doses, allergies, major conditions, doctors and an emergency contact. Store it where responders can find it, such as on the refrigerator or in a labeled folder by the door. Our guide to important documents to protect for emergencies covers keeping copies safe. People who take blood thinners should list them clearly, because this affects stroke treatment decisions.
Plan for building access
High-rise and walk-up apartments add delays. Think through how paramedics will reach your unit:
- Is the buzzer working, and does the dispatcher need a gate or door code?
- Who can hold the elevator or meet responders at the entrance?
- Is the hallway clear enough for a stretcher?
- Does your building have a doorman or front desk that should be told to expect EMS?
These questions are part of a broader building emergency plan with your neighbors.
Older adults and people living alone
People who live alone face the biggest risk of delay, since there may be no one to notice symptoms. Daily check-in calls or texts with a friend or relative, a medical alert device, and neighbors who know to knock if something seems off can all help. Discuss these options with family members who are older or have heart disease, diabetes or high blood pressure.
After the Emergency
Recovery after a stroke depends on the type, its location in the brain and how quickly treatment started. NINDS describes rehabilitation that may include physical, occupational and speech therapy. Family members often become part of the care team.
For caregivers, it helps to ask the hospital team about follow-up appointments, medication changes and the warning signs of a second stroke. Because someone who has had a stroke or TIA is at higher risk of another, the whole household should keep BE FAST fresh in mind.
Quick Reference
| Sign | What to check |
|---|---|
| B, Balance | Sudden dizziness, loss of balance or trouble walking |
| E, Eyes | Sudden vision loss or double vision |
| F, Face | Ask them to smile; one side droops |
| A, Arms | Ask them to raise both arms; one drifts down |
| S, Speech | Slurred or strange speech, trouble understanding |
| T, Time | Call 911 now and note when symptoms began |
Frequently Asked Questions
What if the symptoms go away after a few minutes?
Call 911 anyway. Symptoms that disappear may be a transient ischemic attack, which the CDC describes as a warning sign of a future stroke. It needs emergency evaluation.
Should I give someone aspirin if I think they are having a stroke?
No, not unless a medical professional tells you to. Some strokes are caused by bleeding in the brain, and aspirin could make that worse. Doctors need imaging to know which type it is.
Can young people have strokes?
Yes. Strokes are more common with age, but the CDC notes that they can occur at any age. Treat stroke signs as an emergency no matter how old the person is.
Why is the time symptoms started so important?
Some treatments for ischemic stroke can only be given within a limited window after symptoms begin. Telling responders when the person was last known to be normal helps doctors decide what treatment is possible.
Is it better to drive to the hospital to save time?
The American Stroke Association recommends calling 911. Paramedics can start care, notify the hospital ahead of time and take the person to a stroke-capable hospital.
The Bottom Line
Learn BE FAST: balance, eyes, face, arms, speech and time. If you see any sudden sign, call 911, say “possible stroke,” note when symptoms started and stay with the person without giving food, drink or aspirin. Keep a medication sheet for every household member, plan how responders will reach your apartment, and make sure everyone in your home knows the signs.
