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0861 ©2009 The Johns Hopkins Hospital
The Johns Hopkins Hospital
Patient Information
9/14/09
Interdisciplinary
Clinical Practice
Manual
MDU023 Appendix C
Warfarin: Guide for Patients and
Families
Why do I have
to take
warfarin?
• Warfarin is an effective medicine to prevent new blood clots and to keep existing
ones from getting bigger. It does not dissolve existing clots. Your body does that
naturally.
• A blood clot can slow or stop the flow of blood. Blood clots can cause pain in
your legs (known as DVT) or chest (known as PE). Clots can also cause stroke,
disability, or death. Prompt treatment is important.
• Warfarin may be used in people who have conditions such as;
o atrial fibrillation (irregular heart rhythm)
o DVT (Deep Vein Thrombosis or a blood clot in a vein)
o heart attacks
o heart valve replacements
o peripheral vascular disease (build up of plaque in blood vessels of the legs)
o pulmonary embolism (blood clot in your lung)
o stroke
o valvular heart disease (any problem with one of the four valves in the heart)
o Pulmonary hypertension (high blood pressure in the arteries that supply the
lungs)
• Warfarin is safe and effective if used carefully, but it’s a balancing act. Too much
can cause a dangerous amount of bleeding; too little can allow new clots to form.
The right level is important.
Get your INR
Blood Tests:
• Go for your INR blood tests at least once a month. Many people get tested as
often as once a week when first started on warfarin.
• At every visit, always ask for your INR number and know what your target
range is supposed to be. It may be 2.0-3.0; 2.5-3.5; or even higher. But a number
that’s too high shows more risk for bleeding. A number that’s too low shows
more risk of clots.
• The amount of warfarin you take may change when your INR number changes.
This will help keep your warfarin at the right level.
Take the right
medicines:
• Warfarin has other brand names, Coumadin® and Jantoven™. Do not take
Coumadin® or Jantoven™ in addition to warfarin. This will double your dose
and can be unsafe.
• Warfarin medicines are color-coded by strength. If you get a different color
tablet than usual, ask your doctor or pharmacist about it. To simplify the process,
it’s best to use just one pharmacy.
• Try to avoid taking other medicines that can make you bleed more easily. These
include aspirin, Motrin, ibuprofen, Aleve or naproxen.
• Read all new medicine labels to make sure they don’t contain aspirin before
using them. If you’re not sure, ask your doctor or pharmacist.
• Tylenol (acetaminophen) is usually OK to take, but check with your doctor first.
• If you miss a dose of warfarin do not take an extra pill to “catch up”
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Talk to your
doctor:
• Always ask if any new medicine is safe to take with warfarin. This includes
prescribed medicines, especially antibiotics and over-the-counter medicines. It
also includes vitamins, herbal supplements and nutritional supplements such as
Ensure, Boost, and Slim-Fast.
• Tell all your healthcare providers that you take warfarin. This includes your
physician, nurse, dentist, chiropractor, naturopath and pharmacist. They all need
to know.
• Stopping or changing the amount of other medicines you take can affect your
warfarin levels.
Avoid alcohol
and street
drugs:
• Alcohol can make you bleed more easily while taking warfarin.
• If you do drink alcohol, limit your intake. Drink no more than one 12-ounce beer
or one 6-ounce glass of wine, or one mixed-drink, or one shot of hard liquor in 24
hours. Binge drinking is not good for you.
• Cocaine, heroin and other street drugs can increase your risk of bleeding.
Cuts, Bruises
and
Nosebleeds:
• Warfarin makes you bruise easily. If you bump into something, apply pressure to
the spot, or hold ice on it for 2 to 5 minutes. If the bruise is bigger than 3 inches
across, or keeps getting bigger, go right to the nearest Emergency Department.
Tell them you take warfarin. The bleeding needs to be controlled.
• For a cut, put pressure on the area for 2 to 5 minutes. If you’re still bleeding in 20
to 30 minutes, or it’s a large cut, go right to the nearest Emergency Department.
Tell them you take warfarin.
• If you get a nosebleed, do not hold your head back. Instead, hold your head in a
normal upright position. Pinch your nose together just below the boney part and
squeeze tightly for 2 to 5 minutes. Try a nasal decongestant spray like Afrin or
Neo-Synephrine (if OK with your doctor) to help stop the bleeding. If you’re still
bleeding in 20 to 30 minutes, go to the nearest Emergency Department. Tell them
you take warfarin.
• If you get nosebleeds easily, try using a humidifier, and a saline nasal spray or
gel. This can help keep your nose moist and prevent nosebleeds.
Go straight to
the Emergency
Department if
you:
• Are in a vehicle accident, or have a major fall.
• Notice bright red blood in the toilet after you go to the bathroom, or if your urine
turns smoky pink or red color.
• Notice that your stools are black and sticky, like tar. They may also smell
unusually bad.
• If you are throwing up dark or bloody colored stomach contents.
• Get a sudden and extremely painful headache. It might feel worse than any other
headache in your life.
• Have problems similar to the last time a blood clot formed in your body.
• Briefly black out, can’t move, have trouble talking or become very weak –
especially if you’re weak on only one side of your face or body. This could be a
stroke.
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Diet and
Exercise:
• Some foods you eat contain vitamin K which can work against the warfarin. The highest
amount of vitamin K (which helps the blood to clot) is found in foods such as dark green
leafy vegetables. Foods with high amounts of vitamin K include spinach, broccoli,
cabbage, kale, brussel sprouts and collards. Some meats such as beef and pork liver also
contain high amounts of vitamin K. It is important not to change your vitamin K intake.
Please see the Vitamin K Food Chart on page 4 for more information.
• Keep your diet consistent in the amount of foods that contain vitamin K each day. It is
not necessary to try to eliminate the foods from your diet.
• Call your doctor if you are unable to eat for several days, have vomiting or diarrhea that
last more than one day.
• Keep your exercise level regular
• Maintaining regular daily activities including consistent eating and exercise habits will
make it less likely to need to change your dose of warfarin.
For more about
how to prevent
and treat blood
clots:
• Visit www.clotcare.com and www.nattinfo.org
• If needed, visit the Patient/Staff Library at The Johns Hopkins Hospital or your local
library for Internet access.
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Vitamin K Food Chart
USDA National Nutrient Database for Standard Reference, Release 18
12/01/08
Eat as many low Vitamin k foods as you would like. For foods with medium to high amounts of Vitamin
K, don’t eat more or less of those than you would normally do in a week. For example. If you usually eat
broccoli three times a week, don’t suddenly change your diet and eat broccoli everyday. A steady diet is
key. If you have any questions, please talk to your health care provider.