Definition:
A small cell in the blood that forms an important part of the clotting mechanism.
When damage occurs to a blood vessel, chemicals are released which activate platelets and begin the process of blood clotting.
Activated platelets become "sticky" and adhere to one another, creating a physical barrier that forms a blockage to the flow of blood. Sticky masses of platelets are the primary component of blood clots.
The clotting action of platelets can be disabled, and several types of drugs have been designed to accomplish this. These drugs are given to prevent heart attacks and strokes in "at risk" patients.
