Dr. MJ Bazos MD,
Excessive Blood Clotting
What does hypercoagulation mean?
When you get a cut, your body stops the bleeding
by forming a blood clot (a thickened mass). Substances in your blood (called
proteins) work with tiny particles (called platelets) to form the clot. Forming
a clot is called "coagulation." Coagulation helps when you are injured because
it slows blood loss. However, your blood shouldn't clot when it's moving through
your body. If blood clots inside your blood vessels, it's called "thrombosis" or
"phlebitis." The tendency to clot too much is called "hypercoagulation." It can
be very dangerous.
Why is hypercoagulation dangerous?
When abnormal clots occur, they usually form
inside veins (the vessels that carry blood to the heart). A clot inside a blood
vessel is called a "thrombus." Sometimes the thrombus can travel in the
bloodstream and get stuck in your lungs. This kind of clot, called a "pulmonary
embolus," keeps blood from getting to your lungs. A pulmonary embolus can be
A clot that blocks a blood vessel in the brain
can cause a stroke. A clot in a blood vessel in the heart can cause a heart
attack. Blood clots can cause some women to have miscarriages.
What causes hypercoagulation?
Certain situations or risk factors can make it
easier for your blood to clot too much. These situations include the following:
- Sitting on an airplane or in a car for a long
- Having prolonged bed rest (several days at a
- Having surgery
- Having cancer
- Being pregnant
- Using birth control pills
Some people are born with a
tendency to develop clots. This tendency is inherited (it comes from your
parents). Most of the time, increased clotting happens because the anti-clotting
protein C in the blood isn't doing its job properly.
In some people, the blood clots too much because
their body doesn't make enough anti-clotting protein C or protein S, or they
have antithrombin III (another type of protein) that doesn't work. Some people
have an extra protein in their blood that causes too much clotting.
Hypercoagulation has a few other causes, but those causes are rare.
How do I know if I have a problem
Your doctor might think that you have a problem
with hypercoagulation if you have any of the following:
- You have relatives with abnormal or excessive
- You had an abnormal clot when you were young
- You got clots when you were pregnant or were
using birth control pills
- You have had several unexplained miscarriages
If your doctor suspects you
have hypercoagulation, tests can check the proteins in your blood. The tests
will also show if your proteins are working the right way.
Can hypercoagulation be treated?
Yes. Several medicines can thin your blood and
make it less likely to clot. Some people with hypercoagulation only need to take
blood thinners when they're in a situation that makes them more likely to form
clots--like when they're in the hospital recovering from surgery, when they're
in a car or airplane for a long time and when they're pregnant. Other people
need to take medicine for the rest of their lives. Your doctor will decide which
group you're in.
What medicines are used to treat
The two most common blood thinners are called
heparin and warfarin (brand name: Coumadin). Your doctor will probably give you
heparin first, because heparin works right away. Heparin must be injected with a
small needle under the skin. Once the heparin starts working, your doctor will
probably have you start taking oral warfarin. Warfarin takes longer to begin
What are the side effects of these
Both medicines can cause you to bleed more
easily. You might notice that if you cut yourself, the blood takes longer to
clot. You might bruise more easily. If you have any unusual or heavy bleeding,
call your doctor.
Warfarin has a stronger effect on some people
than on others. If you take warfarin, your doctor will want to check you often
with a blood test called the PT-INR. This test will tell your doctor how well
the warfarin is working. Some other medicines can make warfarin more or less
strong. Ask your doctor before you take a new medicine, even nonprescription
medicines and vitamins.
If you're pregnant, you shouldn't take warfarin.
Warfarin can cause birth defects. Instead, you must use heparin until you have
your baby. If you want to get pregnant and you're already taking warfarin, talk
with your doctor about changing to heparin. Sexually active women who take
warfarin should use birth control.