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Blood clot formation

Blood clot formation

Overview

Blood clotting normally occurs when there is damage to a blood vessel. Platelets immediately begin to adhere to the cut edges of the vessel and release chemicals to attract even more platelets. A platelet plug is formed, and the external bleeding stops.

Next, small molecules, called clotting factors, cause strands of blood-borne materials, called fibrin, to stick together and seal the inside of the wound. Eventually, the cut blood vessel heals and the blood clot dissolves after a few days.

Review Date 4/18/2023

Updated by: John Roberts, MD, Professor of Internal Medicine (Medical Oncology), Yale Cancer Center, New Haven, CT. He is board certified in Internal Medicine, Medical Oncology, Pediatrics, Hospice and Palliative Medicine. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.