We all know how serious and devastating a stroke can be. But would you be able to spot if you or someone else was having one?

According to a new study, a whopping 75 percent of Americans under the age of 45 don't know the signs and symptoms of a stroke. More alarming is that many report they may wait out the symptoms.

"Ignoring or waiting out the symptoms of a brain episode can have fatal consequences," said Margy Kester, Stroke Coordinator at Scranton's Geisinger-Community Medical Center. "The reason it's so important to know the signs of a stroke is that can help you identify if someone is having one and get them successfully treated."

The first three hours are the most important when it comes to a stroke - three hours after an individual begins experiencing symptoms of a stroke, a.k.a. the "golden window," is the period of time when doctors are more successful in minimizing or reversing damage by restoring blood flow to the brain.

"Leaving a stroke untreated or delaying treatment can lead to death or permanent disability," Kester said.

Here are the signs and symptoms that signal you or someone else may be suffering a stroke.

  • Sudden weakness or numbness in your face, arm, or leg on one side of your body
  • Abrupt loss of vision, coordination, strength, speech, sensation, or the ability to understand speech
  • Sudden loss of balance
  • Vomiting, nausea, fever, hiccups or trouble swallowing
  • Sudden vision dimness, especially in one eye
  • Sudden and severe headache with no apparent cause, followed by rapid loss of consciousness
  • Sudden falls or unexplained dizziness

"All of those symptoms may be difficult to remember, which may explain why so many Americans report not knowing the signs of a stroke," Kester said. "Instead of remembering a whole list of symptoms, think of the acronym F.A.S.T."

F.A.S.T. stands for face drooping, arm weakness, speech difficulty, and time to call 911.

"Look to see if one side of the face is drooping or numb. Ask the person to smile to see if their smile is uneven," Kester said.

If one arm is weak or numb, it's another sign of a potential stroke. If you suspect someone is having a stroke, ask them to raise both arms to see if one arm drifts down.

"Another telltale sign of a stroke is slurred speech - is the person unable to speak or hard to understand? Ask them to repeat a simple sentence to tell if their speech is affected," Kester explained.

And if you see any of these symptoms, the "T" in F.A.S.T. becomes imperative.

"If someone is experiencing any of these symptoms, even if they seem to go away, call 911 immediately," Kester said. "Getting to the hospital right away is crucial in preventing serious disability or death."