Reprints
A single copy of this article may be reprinted for personal, noncommercial use only.
Blood thinners: Can I still get blood clots?
By Mayo Clinic staffOriginal Article: http://www.mayoclinic.com/health/blood-thinners/AN01304
- With Mayo Clinic cardiologist
Martha Grogan, M.D.
read biographyclose windowBiography of
Martha Grogan, M.D.
Martha Grogan, M.D.
Dr. Martha Grogan is board-certified in internal medicine and cardiovascular diseases. She is a native of Cincinnati, Ohio, and received her medical degree from Northwestern University Medical School. Dr. Grogan has been on staff at Mayo Clinic since 1995 and is a consultant in the Division of Cardiovascular Diseases and is an assistant professor of medicine at Mayo Medical School.
Dr. Grogan is a noninvasive cardiologist specializing in heart failure, adult congenital heart disease and echocardiography. She has witnessed firsthand the importance of patient education in the treatment of diseases such as congestive heart failure and is excited about the tremendous educational opportunities now available through the Internet.
Free
E-newsletter
Subscribe to Housecall
Our weekly general interest
e-newsletter keeps you up to date
on a wide variety of health topics.
Mayo Clinic Housecall
Stay up to date on the latest health information.
What you get
- Free weekly e-newsletter
- Mayo Clinic expertise
- Recipes, tools and other helpful information
- We do not share your e-mail address
Question
Blood thinners: Can I still get blood clots?
If you're taking a blood thinner, is it still possible for you to get a blood clot?
Answer
from Martha Grogan, M.D.
Yes. Medications that are commonly called blood thinners — such as aspirin, warfarin (Coumadin, Jantoven), dabigatran (Pradaxa), rivaroxaban (Xarelto) and heparin — significantly decrease your risk of blood clotting, but will not decrease the risk to zero. These medications must be taken exactly as directed to work safely and effectively. Taking too little of these medications may not be effective, and taking too much can lead to serious bleeding.
Also, blood thinners may not be able to lessen the strong blood-clotting tendency of an underlying disease, such as cancer.
Interactions with other medications, food and alcohol are common with blood-thinning medications, especially warfarin. These interactions may decrease the effectiveness of your blood thinner, making you more likely to develop blood clots. If you take a blood thinner, be sure to follow your doctor's advice on dosing and ask about foods and other medications — including over-the-counter drugs and herbal supplements — that may interfere with the blood thinner.
- Hirsch J, et al. American Heart Association/American College of Cardiology Foundation guide to warfarin therapy. Journal of the American College of Cardiology. 2003;41:1633.
- Blood thinner pills: Your guide to using them safely. Agency for Healthcare Research and Quality. http://www.ahrq.gov/consumer/btpills.htm. Accessed Feb. 17, 2012.
- Cunningham MS, et al. Does antithrombotic therapy improve survival in cancer patients? Blood Reviews. 2009;23:129.
Find Mayo Clinic on