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Summary
Normally, if you get hurt, your body forms a blood clot to stop the bleeding. After the bleeding stops and healing takes place, your body usually breaks down and removes the clot. But some people get too many clots or their blood clots abnormally. Many conditions can cause the blood to clot too much or prevent blood clots from dissolving properly.
Risk factors for excessive blood clotting include
- Certain genetic disorders
- Atherosclerosis
- Diabetes
- Atrial fibrillation
- Overweight, obesity, and metabolic syndrome
- Some medicines
- Smoking
- Staying in one position for a long time, such as being in the hospital or taking a long car or plane ride
- Cancer and cancer treatments
Diagnosis and Tests
- Antithrombin Test (American Association for Clinical Chemistry)
-
Coagulation Factor Tests
(National Library of Medicine) Also in Spanish
- D-dimer Test (American Association for Clinical Chemistry)
- Factor V Leiden Mutation and PT 20210 Mutation Test (American Association for Clinical Chemistry)
- Fibrinogen Test (American Association for Clinical Chemistry)
-
MPV Blood Test
(National Library of Medicine) Also in Spanish
-
Partial Thromboplastin Time (PTT) Test
(National Library of Medicine) Also in Spanish
-
Protein C and Protein S Tests
(National Library of Medicine) Also in Spanish
- PT and INR Test (American Association for Clinical Chemistry)
- Thrombin Time (American Association for Clinical Chemistry)
Treatments and Therapies
-
Blood Thinners: MedlinePlus Health Topic
(National Library of Medicine) Also in Spanish
- Catheter-Directed Thrombolysis (Radiological Society of North America) Also in Spanish
Related Issues
- Blood Clots and Travel: What You Need to Know (Centers for Disease Control and Prevention) Also in Spanish
- Blood Thinners: Can I Still Get Blood Clots? (Mayo Foundation for Medical Education and Research) Also in Spanish
-
Important Information to Know When You Are Taking: Warfarin (Coumadin) and Vitamin K
(National Institutes of Health, Clinical Center) - PDF Also in Spanish
- Understand Your Risk for Excessive Blood Clotting (American Heart Association)
Specifics
-
Antiphospholipid Syndrome
(National Institute of Neurological Disorders and Stroke)
- Cerebral and Sinus Vein Thrombosis (American Heart Association)
- Factor V Leiden (Mayo Foundation for Medical Education and Research) Also in Spanish
- Hypercoagulation (American Academy of Family Physicians) Also in Spanish
- Thrombophilia and Hypercoagulability (American Heart Association)
- Thrombophlebitis (Mayo Foundation for Medical Education and Research) Also in Spanish
-
Thrombotic Thrombocytopenic Purpura
(National Heart, Lung, and Blood Institute)
-
What Is Antiphospholipid Antibody Syndrome?
(National Heart, Lung, and Blood Institute)
-
What Is Disseminated Intravascular Coagulation?
(National Heart, Lung, and Blood Institute)
Genetics
-
Genetics Home Reference: antiphospholipid syndrome
(National Library of Medicine)
-
Genetics Home Reference: factor V Leiden thrombophilia
(National Library of Medicine)
-
Genetics Home Reference: hereditary antithrombin deficiency
(National Library of Medicine)
-
Genetics Home Reference: protein C deficiency
(National Library of Medicine)
-
Genetics Home Reference: protein S deficiency
(National Library of Medicine)
-
Genetics Home Reference: prothrombin thrombophilia
(National Library of Medicine)
-
Genetics Home Reference: warfarin resistance
(National Library of Medicine)
-
Learning about Antiphospholipid Syndrome (APS)
(National Human Genome Research Institute)
-
Learning about Factor V Leiden Thrombophilia
(National Human Genome Research Institute)
Videos and Tutorials
-
Blood clotting
(Medical Encyclopedia) Also in Spanish
Clinical Trials
-
ClinicalTrials.gov: Thrombophlebitis
(National Institutes of Health)
-
ClinicalTrials.gov: Thrombosis
(National Institutes of Health)
-
ClinicalTrials.gov: Venous Thrombosis
(National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
Find an Expert
- Centers for Disease Control and Prevention Also in Spanish
- Find a Hematologist (American Society of Hematology)
-
National Heart, Lung, and Blood Institute
Children
- Blood (For Parents) (Nemours Foundation) Also in Spanish
Women
- Postpartum Blood Clots (Merck & Co., Inc.) Also in Spanish
Patient Handouts
- Arterial embolism (Medical Encyclopedia) Also in Spanish
- Blood clots (Medical Encyclopedia) Also in Spanish
- D-dimer test (Medical Encyclopedia) Also in Spanish
- Prothrombin time (PT) (Medical Encyclopedia) Also in Spanish
- Superficial thrombophlebitis (Medical Encyclopedia) Also in Spanish
- Thrombophlebitis (Medical Encyclopedia) Also in Spanish