Examples
Coumarins
| Generic Name | Brand Name |
|---|
| warfarin | Coumadin |
Low-molecular-weight heparins (LMWH)
| Generic Name | Brand Name |
|---|
| dalteparin | Fragmin |
| enoxaparin | Lovenox |
| tinzaparin | Innohep |
Antithrombotic medications
| Generic Name | Brand Name |
|---|
| fondaparinux | Arixtra |
Unfractionated heparins (UH)
How It Works
Anticoagulant medications (also known as blood thinners) help
prevent the formation of blood clots by increasing the time it takes a blood
clot to form. This prevents a clot that has already formed from getting larger
and reduces the chances that pieces of a clot will break off and cause a
heart attack or
stroke.
Why It Is Used
Anticoagulants are used in the treatment of
mitral valve regurgitation and
aortic valve regurgitation:
- When
atrial fibrillation is present.
- After
valve surgery. At this time there is an increased risk for blood clots. If you
have a mechanical valve (made with metal or plastic), you will have to take
anticoagulants for the rest of your life.
After heart valve replacement surgery, both Coumadin (warfarin) and
one of several types of anticoagulant medications—a low-molecular-weight
heparin, an unfractionated heparin, or an antithrombotic medication—are
started. Coumadin is given in pill form while the other medications are given
as a shot. The injected medications (low-molecular-weight heparin,
unfractionated heparin, and antithrombotic medications) act immediately, while
Coumadin takes several days to become effective. Once Coumadin begins to work,
the other medications are stopped.
How Well It Works
Anticoagulants prevent clotting of a mechanical heart valve.
Anticoagulants have also been shown to reduce the risk of stroke in people who
have atrial fibrillation.1, 2
Side Effects
Anticoagulants may cause:
- Easy bruising.
- Bleeding in the
brain.
- Bleeding in the stomach and intestines.
- Skin
rash.
See Drug Reference for a full list of side effects. (Drug Reference
is not available in all systems.)
What To Think About
If you are taking anticoagulants, notify your doctor immediately if
you:
- Have unusual bruising or red or purple spots on
the skin.
- Have unusual bleeding from the nose or gums, or if you
are spitting up blood.
- Have blood in your urine.
- Have
red or black (tarry) stools.
- Have been vomiting blood or material
that looks like coffee grounds.
- Have abnormally long menstrual
periods.
Safety tips when taking anticoagulants may be helpful,
such as taking your medications at the same time each day and watching for
signs of bleeding.
What to do if you miss a dose of anticoagulant.
- If you remember it in the same day, take the
missed dose. Then go back to your regular schedule.
- If it is the
next day, or almost time to take the next dose, do not take the missed dose. Do
not double the dose to make up for the missed one. At your next regularly
scheduled time, take your normal anticoagulant dose.
- If you miss
your dose for 2 or more days, call your doctor.
Do not double the dose in any one day to make up for a missed
dose.
Call your doctor if you are not sure what to do if you missed a
dose.
You will need to have your blood drawn frequently while taking some
anticoagulant medications. Anticoagulant therapy requires regular monitoring
because high levels of anticoagulants increase the risk of bleeding, while
levels that are too low increase the risk of stroke and heart attack.
Women have a higher incidence of bleeding while taking
anticoagulants than do men and require more frequent monitoring.3
Some anticoagulants pose a definite risk to a fetus. Pregnant women
are generally not advised to take Coumadin (warfarin), because it is known to
cause birth defects. If you become pregnant while taking Coumadin, your doctor
may recommend that you switch to a low-molecular-weight form of heparin
(another anticoagulant) during the first and third
trimesters of your pregnancy, and take Coumadin only
during the second trimester. Long-term use of these heparin formulations is not
recommended, because it is associated with
osteoporosis and
thrombocytopenia.
Always talk to your health professional before using any
anticoagulant during pregnancy or if you become pregnant while using them.
Check with your doctor immediately if you are taking an anticoagulant and think
you may be pregnant.
Anticoagulants interact with other medications and foods. Talk to
your doctor or pharmacist about possible interactions anticoagulants may have
with your current medications.
Special care should be taken when you shave and when brushing and
flossing your teeth:
- Use only a soft toothbrush and floss very
gently.
- Use an electric razor instead of a blade.
Do not drink alcohol while taking anticoagulant medications.
Alcohol can change the way an anticoagulant works.
Do not participate in contact sports or other potentially hazardous
activities while taking anticoagulant medications. Report any falls, blows to
the body or head, or other injuries to your doctor immediately.
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to help you understand this medication.