D-Dimer Test Test
A D-dimer test checks for a protein fragment in your blood that is made when a blood clot dissolves. It helps find out if you may have a blood clotting disorder.
What this test measures
The D-dimer test looks for D-dimer, a protein fragment that is made when a blood clot dissolves in your body. Normally, D-dimer is not found in your blood unless your body is making or breaking up blood clots.
What your results mean
Reference ranges vary by laboratory and by your age and sex. MedlinePlus does not publish a single normal range for this test — always read your result against the range printed on your own lab report and discuss it with your provider.
Higher-than-normal results
Higher than normal levels of D-dimer may be a sign of a clotting disorder. Additional tests will be needed to show where the blood clot is located or what type of clotting disorder you have. High D-dimer levels can also be caused by pregnancy, heart disease, rheumatoid arthritis, recent surgery, being older, or being immobilized.
Lower-than-normal results
Low or normal D-dimer levels in the blood mean you probably don't have a clotting disorder.
Frequently asked questions
What is a D-dimer test?
A D-dimer test looks for D-dimer in your blood. D-dimer is a protein fragment made when a blood clot dissolves.
Why is a D-dimer test done?
It is used to check if you may have a blood clot and to see if you need more tests for blood clotting disorders.
What does a normal D-dimer result mean?
If your results show low or normal D-dimer levels, it means you probably don't have a clotting disorder.
What does a high D-dimer result mean?
High D-dimer levels may be a sign of a clotting disorder, but they can also be caused by pregnancy, heart disease, rheumatoid arthritis, recent surgery, being older, or being immobilized.
Can medicines affect D-dimer test results?
Yes, blood thinner medicines may cause a false negative D-dimer test, meaning the test shows no clotting disorder when you actually have one.
Related lab tests
Sources
- MedlinePlus: D-Dimer Test — NIH MedlinePlus
Last updated . Information is aggregated from official public sources and is not a substitute for professional medical care.