Warfarin is a very important an d widely-used drug in preventing the
formation of life-threatening blood clots. In 2005, there were 22
million prescriptions filled for
the drug. However, it interacts with
a number of other drugs, dietary supplements, and vitamins. When used
improperly, warfarin can lead to
potentially life-threatening bleeding
episodes. The medications with which warfarin interacts are
inexplicably not listed in the Medication
Guide. In our book, Worst Pills, Best
Pills and on our website, Worstpills.org, we have warned about these serious
interaction problems, list the interacting
drugs, and have continually
updated the information.
The FDA has the regulatory authority to require the
distribution of
Medication Guides by pharmacists for drugs that pose a serious and
significant public health concern. However, at this time, there are
only approximately 75 drugs that require Medication Guides out of the
thousands of drugs on the market. A list of these drugs with links
to
their respective Medication Guides can be found on the FDA's Web site
at: http://www.fda.gov/cder/Offices/ODS/medication_guides.htm.
The new warfarin Medication Guide is reproduced below.
MEDICATION GUIDE
COUMADIN(COU-ma-din) Tablets
(Warfarin Sodium Tablets, USP) Crystallin
Read this Medication Guide before you start taking COUMADIN
(Warfarin
Sodium) and each time you get a refill. There may be new information.
This Medication Guide does not take the place of talking to your
healthcare provider about your medical
condition or treatment. You and
your healthcare provider should talk about COUMADIN when you start
taking it and at regular checkups.
What is the most important information I should know
about COUMADIN?
Take your COUMADIN exactly as prescribed to lower the
chance of blood
clots forming in your body. (See "What is COUMADIN?").
COUMADIN is very important for your health, but it can
cause serious
and life-threatening bleeding problems. To benefit from COUMADIN and
also lower your chance for bleeding problems, you must:
Get your
regular blood test to check for your response to
COUMADIN. This blood test is called a PT/INR test. The PT/INR test
checks to see how fast your blood
clots. Your healthcare provider will
decide what PT/INR numbers are best for you. Your dose of COUMADIN will
be adjusted to keep your PT/INR in
a target range for you.
Call your
healthcare provider right away if you get any of the
following signs or symptoms of bleeding problems:
pain, swelling
or discomfort
headaches, dizziness, or weakness
unusual bruising (bruises
that develop without known cause or
grow in size)
nose bleeds
bleeding gums
bleeding from cuts takes a long time to stop
menstrual bleeding or vaginal bleeding that is heavier
than
normal
pink or brown
urine
red or black stools
coughing up blood
vomiting
blood or material that looks like coffee grounds
Many other medicines, including prescription and non-prescription
medicines, vitamins and herbal supplements
can interact with COUMADIN
and:
affect the dose you need,
or
increase
COUMADIN side effects.
Tell your healthcare provider about all the medicines
you take. Do not
Stop medicines or take anything new unless you have talked to your healthcare
provider. Keep a list of your medicines with you at all times to show
your healthcare provider and pharmacist.
Do not take other medicines that contain warfarin. Warfarin is the active ingredient in COUMADIN. Some foods can interact
with COUMADIN and affect your treatment and dose.
Eat a normal,
balanced diet. Talk to your doctor before you
Make any diet changes. Do not eat large amounts of leafy green vegetables.
Leafy green vegetables contain Vitamin
K. Certain vegetable oils also
contain large amounts of Vitamin K. Too much Vitamin K can lower the
effect of COUMADIN.
Avoid drinking
cranberry juice or eating cranberry products.
Avoid drinking alcohol.
Always tell all of your healthcare providers that you
take COUMADIN.
Wear or carry information that you take COUMADIN.
What is COUMADIN?
COUMADIN is an anticoagulant medicine. It is used to
lower the chance
of blood clots forming in your body. Blood clots can cause a stroke,
heart attack, or other serious conditions such as blood clots in the
legs or lungs.