A stroke is a medical emergency caused by an obstruction that blocks or partially blocks blood flow to the brain, depriving brain tissue of oxygen and nutrients. Within a matter of minutes, brain cells begin to die. A stroke may be caused by a blocked artery (ischemic stroke) or a leaking or burst blood vessel (hemorrhagic stroke). Symptoms include trouble walking, speaking and understanding; paralysis or numbness of the face, arm or leg; vision problems and headaches. Certain risk factors may contribute to the development of a stroke, such as being overweight or obese, cardiovascular disease, cigarette smoking, diabetes, binge drinking, high blood pressure, sleep apnea, genetics and physical inactivity. Medication, frequent monitoring, therapy and rehabilitation, and lifestyle adjustments can help reduce the risk of brain damage and prevent another stroke from occurring.