How It Works
Normally, when an injury that causes
bleeding occurs, the body sends out signals that cause blood to clot at the
wound, and the clot naturally breaks down as the wound heals. A person prone to
abnormal clotting has an imbalance between clot formation and clot breakdown.
Anticoagulant medicines prevent new clots from forming and
prevent existing clots from growing (extending) by stopping the production of
certain proteins that are needed for blood to clot. They do not break up or
dissolve existing blood clots.
Why It Is Used
Heparin can be used to prevent and
initially treat a
deep vein thrombosis.
When used for
prevention, heparin will be given by injection just under the skin a few hours
before surgery and 2 to 3 times a day for several days after surgery.
When used for treatment, heparin is given through the vein
(intravenously, or IV) in a continuous infusion or by injection just under the
skin two times each day. Also, blood tests will be done at least one
time a day to monitor the effect of the medicine.
is given through an IV, it can be turned off quickly. This method is safe for
people who might bleed or need procedures done in an emergency.
How Well It Works
Heparin can be used to treat or
prevent a deep vein thrombosis. When used for treatment, heparin prevents new
blood clots from forming and prevents existing clots from getting larger. This
allows the normal body systems to dissolve the clots that are already
Heparin reduces the chance that a blood clot will get
larger. This reduces the risk of getting a blood clot in the lung (pulmonary
Unfractionated heparin works well to treat and prevent
deep vein thrombosis. But there are times when a doctor might use
low-molecular-weight heparin, especially in people who just had orthopedic
Bleeding is the most common side effect
of heparin. This may include:
- Bleeding from an undiagnosed ulcer or growth in the digestive
- Serious bleeding in other areas because of an injury or
- Serious bleeding that can occur in the brain, resulting in death
If you are taking an anticoagulant and you see
signs of bleeding, notify your doctor immediately.
side effects include:
- Rarely, a blood disorder called
- Localized irritation,
pain, or bruising at the location where it is given.
- Bone loss,
which may occur as a side effect of heparin use that lasts 1 month or more.
Heparin is rarely given for longer than 3 to 7 days. But longer treatment is
sometimes required when a person cannot take warfarin (such as during
See Drug Reference for a full list of side effects. (Drug
Reference is not available in all systems.)
What To Think About
Call your doctor immediately if
you are bleeding and it does not stop when you apply pressure.
Unfractionated heparin (UH) is given through a vein (intravenously, or
IV) or injected under the skin.
Pregnant women can take
unfractionated and low-molecular-weight heparin but not warfarin, an oral
You will need to take precautions to avoid bleeding problems while you are taking heparin. These precautions include:
People with active stomach ulcers or severe liver or kidney
disease probably should not take anticoagulants.
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