A stroke can occur when blood flow to the brain is blocked or there is sudden bleeding in the brain. There are two types of strokes. A stroke that occurs because blood flow to the brain is blocked is called an ischemic stroke. The brain cannot get oxygen and nutrients from the blood. Without oxygen and nutrients, brain cells begin to die within minutes. A stroke that occurs because of sudden bleeding in the brain is called a hemorrhagic stroke. The leaked blood results in pressure on brain cells, damaging them.

Just under 90% of strokes involve blocked blood vessels (ischemic), and the rest involve internal bleeding (hemorrhagic). Strokes are further classified based on where in the brain the blockage or bleeding occurs.

A stroke is a medical emergency. A stroke can cause lasting brain damage, long-term disability, or even death. Signs of a stroke can range from mild weakness to paralysis or numbness on one side of the face or body. Other signs may include a sudden and severe headache, sudden weakness, trouble seeing, and trouble speaking or understanding speech.

An ischemic stroke occurs when the blood supply to part of the brain is interrupted or reduced, preventing brain tissue from getting oxygen and nutrients. Brain cells begin to die in minutes.

A stroke is a medical emergency, and prompt treatment is crucial. Early action can reduce brain damage and other complications.

The good news is that many fewer Americans die of stroke now than in the past. Effective treatments can also help prevent disability from stroke.