TPA, a drug used to break up clots in stroke victims, can be a wonderful, life-saving treatment, but it should be used with caution. In fact, two new studies point out that only those doctors who are most skilled in administering TPA should do so. TPA is a complex drug that must be given to stroke victims within three hours of the onset of stroke symptoms. While TPA is very beneficial and might even save lives, if it is administered after the three-hour period, it will not work and may actually harm stroke victims. In addition, TPA must not be given to those who have suffered a hemorrhagic stroke. Hemorrhagic strokes occur when there is bleeding in the brain. TPA may worsen such bleeding.

TPA, short for "tissue plasminogen activator," is made by Genentech and received approval from the Food and Drug Administration in 1996. Almost 600,000 strokes occur each year. TPA has been found to aid stroke victims in about 80% of those cases. Strokes are the third-leading cause of death in the United States, claiming almost 159,000 people each year.

Both studies concluded that doctors who medicate with TPA must follow strict guidelines set out by Genentech and administer the drug to non-hemorrhagic stroke victims within the three-hour window.