If you experience any of these symptoms, call 911.

By Kendall Wenaas
Photo by Getty Images

Every year, almost 800,000 people experience a stroke. Sometimes called a “brain attack,” it occurs when brain cells don’t get enough oxygen. In the U.S., about 80% of strokes are caused by a blood clot that forms in (or travels to) the brain and blocks blood flow. The other 20% are caused by a blood vessel breaking, which causes bleeding that presses against the brain and blocks oxygen flow. If the latter occurs, you’ll likely experience a severe headache. “If you suddenly experience the worse headache of your life, seek help from a medical professional immediately,” says Jose Torres, MD, neurologist at NYU Langone’s Center for Stroke and Neurovascular Diseases.

Besides that, just remember the two acronyms, BE and FAST:

Balance

“If you experience sudden dizziness, loss of balance or are walking like you’re drunk (but you aren’t) that’s a concern,” Torres says.

Eyes

“Anything to do with your eyes, like sudden onset loss of vision, double vision or blurry vision needs to be checked out,” Torres says.

Facial droop

If one side of the face suddenly starts drooping, it could be sign of a stroke.

Arm weakness

When one arm suddenly feels weak, hold them both out in front of you. If one arm drifts down, have someone drive you to the emergency room.

Speech changes

Slurred or incoherent speech isn’t something to take lightly. If you’re worried someone is experiencing a stroke, ask them to repeat a simple sentence. If they struggle, seek medical help immediately.

The T in BE FAST isn’t a symptom, but a reminder. “This letter serves as a reminder to people that if you notice any of these symptoms you need to get to the hospital as soon as possible, time is of the essence in stroke” Torres says. Don’t make an appointment with your doctor—any sign of a stroke is worth a 911 call or visit to the emergency room ASAP.

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