Symptoms
Sutter Stroke Center

Stroke is a medical emergency.  If you or someone you are with exhibits any of the warning signs, call 9-1-1 at once.  Fast treatment is the key to saving lives and preventing disabilities.  The National Institute of Neurological Disorders and Stroke (NINDS) provides the following information on stroke:
Symptoms of stroke appear suddenly. Watch for these symptoms and be prepared to act quickly for yourself or on behalf of someone you are with:

• Sudden numbness or weakness of the face, arm, or leg, especially on one side of the body.
• Sudden confusion, trouble talking, or understanding speech.
• Sudden trouble seeing in one or both eyes.
• Sudden trouble walking, dizziness, or loss of balance or coordination.
• Sudden severe headache with no known cause.

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If you suspect you or someone you know is experiencing any of these symptoms indicative of a stroke, do not wait. Call 9-1-1 emergency immediately. There are now effective therapies for stroke that must be administered at a hospital, but they lose their effectiveness if not given within the first three hours after stroke symptoms appear. Every minute counts!
Depending on the type of stroke (see the About Stroke section of this Web site), stroke symptoms can vary somewhat.  Because of the brain’s two-hemisphere structure, stroke symptoms usually occur on one side of the body.  Ischemic strokes (caused by a blood clot or narrowing of the arteries) usually occur on the side of the body opposite from where the clot is located.  Hemorrhagic strokes also typically affect one side of the body more than the other, but because bleeding in the brain creates pressure, symptoms may also include a severe headache, nausea, neck stiffness, seizures, irritability, and unconsciousness. 
Symptoms most often develop suddenly, but some types of strokes may cause symptoms to develop progressively over a period as long as a few days.  In rare instances, small strokes that happen over time may show up as gradual changes in a person’s ability to function mentally and physically, such as a growing tendency toward confusion, increasing difficulty balancing or walking, or escalating irritability and other behavior changes.
If you notice changes—either sudden or gradual—that appear in the list of symptoms, get immediate medical attention.  Do not be concerned that you might be overreacting.  Stroke is a serious condition that can be treated most effectively if diagnosed early.