A stroke occurs when the blood flow to the brain is interrupted (ischemic stroke) or a blood vessel in the brain bursts (hemorrhagic stroke). In either of these cases, brain cells begin to die because blood can't reach them and they can't get the oxygen and nutrients they need to function.

The other type of stroke is hemorrhagic. It is caused when a blood vessel in the brain breaks and causes bleeding there.

The symptoms of stroke occur suddenly and quickly. Numbness or weakness can also occur in the face and on one side of the body. A person having a stroke may suddenly have difficulty speaking or understanding what someone is saying to them. The person may suddenly have trouble walking and lose his or her balance. Sudden dizziness is another symptom. If you are with someone who is experiencing any of these symptoms, seek medical help right away.

Without counting any other risk factors, smoking almost doubles a younger adult's risk for ischemic stroke, according to the NINDS. Heavy smokers are at greater risk than people who don't smoke as much. In older adults, smoking can be a contributing cause. But high blood pressure, heart disease, and diabetes are stronger risk factors.

Ischemic strokes are treated with a medicine called t-PA. This medicine dissolves blood clots blocking blood flow to the brain, according to the NINDS. To work as it should, the medicine must be given within 3 hours after stroke symptoms start. Because a person who may be having a stroke must be looked at by hospital staff, the NINDS says that the person must arrive at the hospital within an hour after the symptoms start.

Clot-preventing (antiplatelet) and blood-thinner (anticoagulant) medicines help prevent a stroke. Antiplatelet medicine prevents the blood from clotting by affecting how the platelets do their job, according to the NINDS. Reducing the risk for blood clots cuts the risk for ischemic stroke. Aspirin is the most commonly used antiplatelet medicine. Others that work include clopidogrel and ticlopidine. Anticoagulants also make blood less able to clot. Warfarin and heparin are 2 common anticoagulant medicines. Clot-busting (thrombolytic) medicine is given to a person having an ischemic stroke, or within 3 hours after stroke symptoms start. This helps prevent damage.

Most stroke patients need some form of physical and occupational therapy. A person who has had a stroke may need help relearning basic skills such as how to walk, sit, stand, or lie down, according to the NINDS. The person may also need help with eating, drinking, dressing, bathing, cooking, and using the toilet.