Skip to Content
Home > Wellness > Health Library > Warfarin: Taking Your Medicine Safely
Warfarin is a medicine that helps prevent blood clots. Because it prevents clots, it also helps prevent heart attacks, strokes, and other problems caused by blood clots.
It's important to know how to take warfarin safely.
Warfarin causes you to bleed more quickly when you're injured. So be sure to avoid doing things that increase your chances of bleeding. These are the four main steps you need to take:
Regular blood tests will help your doctor make sure you are taking the right amount of warfarin.
Things like an infection or a small change in your diet can change the way warfarin works. So can other medicines that you are taking. That's why regular testing is so important. The tests tell your doctor whether your dose needs to be changed.
Don't change your dose or stop taking warfarin unless your doctor tells you to.
Make these changes in your life to prevent falls:
Make these changes in your home to prevent falls:
Make these changes to prevent injuries:
Taking other medicines along with warfarin can cause a bad reaction. For example, some medicines can change the way warfarin works so you bleed too easily. Or warfarin can change the way the other medicine works.
Talk to your doctor before you start or stop taking any prescription medicines, over-the-counter medicines, vitamins, or herbal products. If other doctors prescribe something for you, be sure they know that you take warfarin. Here are some examples of medicines that you need to be careful of:
Follow these safety tips for taking medicines:
If you miss a dose of warfarin, the best thing to do is call your doctor.
He or she can tell you exactly what to do so you don't take too much or too little. That way you'll stay as safe as possible.
But here are some general rules:
Most people who take warfarin can eat normally. But make sure that you don't suddenly eat a lot more or a lot less food that is high in vitamin K than you usually do.
Vitamin K helps your blood to clot so wounds don't bleed too much.
Warfarin makes blood clots form more slowly. Suddenly changing the amount of vitamin K you eat each day could keep warfarin from working well.
Follow these general rules when you take warfarin:
If you are pregnant, do not take warfarin. Warfarin can cause miscarriage or birth defects. If you are taking warfarin, talk to your doctor about how you can prevent pregnancy.
If you think you might be pregnant, call your doctor. If you are pregnant, you will take heparin during your pregnancy.
If you plan on getting pregnant, talk with your doctor. You and your doctor will decide which medicine you will take—warfarin or heparin—while trying to get pregnant.
Call 911 or other emergency services right away if you have:
Call your doctor now or seek immediate medical care if you have:
If you are injured, apply pressure to stop bleeding. Realize that it
will take longer than you are used to for the bleeding to stop. If you can't get the bleeding to stop, call your doctor.
Other Works Consulted
Agency for Healthcare Research and Quality (2010). Blood Thinner Pills: Your Guide to Using Them Safely (AHRQ Publication No. 09-0086-C). Rockville, MD: Agency for Healthcare Research and Quality. Available online: http://www.ahrq.gov/consumer/btpills.htm.
ByHealthwise StaffPrimary Medical ReviewerE. Gregory Thompson, MD - Internal MedicineSpecialist Medical ReviewerJeffrey S. Ginsberg, MD - Hematology
Current as ofFebruary 20, 2015
Current as of:
February 20, 2015
E. Gregory Thompson, MD - Internal Medicine & Jeffrey S. Ginsberg, MD - Hematology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2015 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Our interactive Decision Points guide you through making key health decisions by combining medical information with your personal information.
You'll find Decision Points to help you answer questions about:
Get started learning more about your health!
Our Interactive Tools can help you make smart decisions for a healthier life. You'll find personal calculators and tools for health and fitness, lifestyle checkups, and pregnancy.
Feeling under the weather?
Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.