A stroke can happen suddenly, and recognizing the warning signs quickly can be critical.

According to the CDC, symptoms can include sudden numbness or weakness in the face, arm or leg—especially on one side of the body—along with sudden confusion, trouble speaking or understanding speech, vision problems, dizziness or loss of balance, or a sudden severe headache with no known cause.

The American Stroke Association recommends remembering B.E. F.A.S.T.:

B — Balance: sudden loss of balance
E — Eyes: sudden vision changes
F — Face: one side of the face may droop
A — Arm: sudden weakness or numbness
S — Speech: difficulty speaking or understanding
T — Time: call 911 immediately if these signs appear.

If you or someone around you develops these symptoms suddenly, call 911 right away rather than waiting to see if they go away.