Patients who have been identified as having a Stroke may be treated at the hospital with a clot-dissolving drug called tPA (tissue plasminogen activator). The U.S. Food and Drug Administration has approved tPA to treat Strokes caused by blood clots (which cause about 85 percent of all Strokes). tPA dissolves the clot and restores blood flow to the brain. It does carry a risk of bleeding in the brain, but when an experienced doctor uses it properly, its benefits far outweigh the risks.
Not every Stroke patient, particularly those having a Hemorrhagic Stroke, should be treated with tPA. That is why it is extremely important to determine the type of Stroke very quickly. tPA is effective only if given promptly — for maximum benefit the therapy must be started within three hours of the onset of Stroke symptoms.