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Warfarin (Coumadin, Jantoven) is a medicine that helps keep your blood from clotting. It is one of several medicines known as blood thinners. This medicine may be important if you have already had blood clots, or if your health care provider is worried that you may form a blood clot.
Below are questions you may want to ask your provider to help you when you take warfarin.
Questions
Why am I taking warfarin?
- What is a blood thinner?
- How does it work?
- Are there alternative blood thinners I could use?
What will be changed for me?
- How much bruising or bleeding should I expect?
- Are there exercises, sports activities, or other activities that are not safe for me?
- What should I do differently at school or work?
How should I take warfarin?
- Do I take it every day? Will it be the same dosage every day? What time of the day should I take it?
- How can I tell the different warfarin pills apart?
- What should I do if I am late for a dose? What should I do if I forget to take a dose?
- How long will I need to take the warfarin?
Can I still take acetaminophen (Tylenol), aspirin, ibuprofen (Advil, Motrin), or naproxen (Aleve, Naprosyn)? What about other pain medicines? How about cold medicines? How about antibiotics? What should I do if a provider gives me a new prescription?
Do I need to make any changes in what I eat or drink or my overall eating habits? Can I drink alcohol?
What should I do if I fall? Are there changes I should make around the home?
What are the signs or symptoms that I may be bleeding somewhere in my body?
Do I need any blood tests? Where do I get them? How often?
Alternative Names
Warfarin - what to ask your doctor; Coumadin - what to ask your doctor; Jantoven - what to ask your doctor
References
Aronson JK. Coumarin anticoagulants. In: Aronson JK, ed. Meyler's Side Effects of Drugs. 16th ed. Waltham, MA: Elsevier; 2016:702-737.
Becker RC, Ortel TL. Antithrombotic and antiplatelet therapy. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 70.
Review Date 3/6/2025
Updated by: Jacob Berman, MD, MPH, Clinical Assistant Professor of Medicine, Division of General Internal Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.