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Platelet

A platelet is the smallest type of blood cell. Platelets are the body's first defense against bleeding, helping the blood to clot (coagulate) by collecting at the site of a wound and clumping together to help stop the flow of blood.

People with very low levels of platelets or with bleeding disorders may need to have transfusions of platelets to prevent excessive bleeding.

Author Caroline Rea, RN, BS, MS
Editor Maria Essig
Associate Editor Tracy Landauer
Primary Medical Reviewer Anne C. Poinier, MD - Internal Medicine
Specialist Medical Reviewer Joseph O'Donnell, MD - Hematology/Oncology
Last Updated September 12, 2008

WebMD Medical Reference from Healthwise

Last Updated: September 12, 2008
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