From the onset of stroke symptoms, time is precious. Getting emergency help within three hours can mean the difference between severe brain damage and full or partial recovery.

If you have any of the following warning signs, call, or have someone call, 911 immediately:

• sudden weakness or numbness in the face, arm or leg
• sudden dimness or loss of vision, particularly in one eye
• sudden difficulty speaking or understanding speech
• sudden severe headache with no known cause
• unexplained dizziness, unsteadiness, or sudden falls, especially in conjunction with the other warning signs

Occasionally, strokes cause double vision, drowsiness, nausea, or vomiting. Also, because warning signs sometimes may last only a few minutes and disappear, it may be tempting to ignore them. But these "mini-strokes," or transient ischemic attacks (TIAs), could be your body's warning of a future full-blown stroke. So even if the symptoms go away quickly, seek medical help right away.