There is no medical condition specifically referred to as a "sleep stroke." However, strokes can occur at any time, including during sleep. A stroke happens when blood flow to the brain is disrupted, either due to a blocked blood vessel (ischemic stroke) or bleeding in the brain (hemorrhagic stroke). The risk factors for stroke include hypertension, diabetes, smoking, and other cardiovascular conditions. If someone experiences symptoms like sudden numbness, confusion, trouble speaking, or severe headache, even during sleep, immediate medical attention is crucial.

Sleep stroke is known as wake-up stroke. It is estimated one in five or 20% of all strokes are wake-up strokes.

It is a stroke which happens in your sleep. Patient wakes up with symptoms of stroke which were not present before falling asleep.