This editorial relies heavily on the article The Management of Anticoagulation Before and After Procedures by John Spandorfer, M.D. in Medical Clinics of North America, Postoperative Medical Complications, 2001;85: 1109-1116.

Warning: Picture is quite graphic.

Pharmacotherapy 23(5):674-677, 2003. © 2003 Pharmacotherapy Publications Registration Required. Posted 05/30/2003

Last Updated: 1/1/2004

Warfarin Institute of America

Warfarin sodium. Official manufacturer's site.

US Pharm. 2007;32(3):HS-35-HS-48. Much of the published clinical data indicate that newer anticoagulants are at least as effective as traditional anticoagulants, and some are more effective (i.e., fondaparinux in orthopedic surgery, hirudin in acute coronary syndromes). DTIs have the potential to decrease bleeding risk, compared with traditional anticoagulants in some circumstances (e.g., bivalirudin in patients given percutaneous intervention). Oral formulations of DTIs are not currently available but are in developmental phases. Oral agents showing promise have the potential to revolutionize antithrombotic therapy, allowing for safer and more convenient administration, as well as equal or superior therapeutic effectiveness. However, to date, warfarin is the only oral agent available in the U.S. for chronic antithrombotic therapy.

Hearing that your child will require warfarin (Coumadin®) therapy can be a frightening experience for parents. With proper information and counseling most fears can be addressed. Your child's physician is a great resource for information. Most, if not all, hospitals will provide parents with information on the use of warfarin before discharging a child. If your child requires frequent monitoring of his or her blood, the clinic in which their blood tests are performed is another good source of information. Remember, "there are no dumb questions, the only dumb question is one that is not asked". Your child's healthcare providers are there to help, so never be afraid to ask a question. With this paper I hope to address questions you may have about warfarin use in children. I have also included stories from parents whose children are on warfarin therapy.

Information about Coumadin

I rather not see a woman who has had a thrombosis associated with oral contraceptives or hormone replacement therapy, who is now on coumadin take the pill or hormones. However, one can make an argument that that it is probably o.k., since the patient is now protected by coumadin. However, if the woman has fluctuating INRs and has low INRs at times (i.e. is below her therapeutic range), the pill or hormones may pose a risk for recurrence of clots. Also, in women with antiphospholipid antibody syndrome, who may be at particularly increased risk for re-clotting, even with therapeutic INRs, I strongly recommend against resuming the pill and hormones. Last Updated: 2/15/2004

A pharmacist explains how Coumadin works, why doctors prescribe this blood thinner, and common side effects of the drug.

Anticoagulation with warfarin is very effective for preventing blood clots. Unfortunately, sometimes a person taking warfarin has a level that is too high. Questions persist about the risks and management of an INR that is too high. The management of bleeding in the over-anticoagulated patient is complex and is based on balancing the risks and benefits of each treatment.

Description of the use and side effects of Coumadin

New study finds conventional- intensity warfarin better than low-intensity at preventing recurrent VTE.

HIRSH et al., AHA/ACC Expert Consensus Document on Warfarin Therapy. JACC 2003;41:1633-52. © 2003 by the American Heart Association, Inc., and the American College of Cardiology Foundation

Links to warfarin/Coumadin sites.

Semin Thromb Hemost. 1999;25(1):79-83. Except for bleeding complications, relevant adverse effects of coumarin anticoagulants are comparatively rare considering the widespread use of these substances. Here we present the case of a 56-year-old woman who developed recurrent episodes of severe hepatitis following repeated exposure to phenprocoumon (Marcumar; Roche, Grenzach-Wyhlen, Germany) and warfarin (Coumadin; DuPont Pharma, Bad Homburg, Germany) after replacement of the mitral valve with a mechanical prosthesis. The diagnosis of "coumarin-induced hepatitis" is compatible with the time relationship between start of the drug and the onset of hepatopathy (first episode 8 months, second episode 4 weeks, and third episode 7 days), the rapid improvement following discontinuation of the drug, recurrence of liver dysfunction after re-exposure to the drug, and liver histology. After anticoagulant therapy was changed to heparin and acenocoumarol (Sintrom; Ciba-Geigy, Basel, Switzerland), the patient's general state was markedly improved and her liver values became almost normal. This case will be discussed and compared with other reports of coumarin-induced hepatic lesions. Although liver damage induced by coumarin derivates is rare, it is important to be aware of the hepatotoxic potential of these drugs, which, in most cases, mimics the clinical presentation of viral hepatitis.

Arch Intern Med. 1985 Mar;145(3):499-501.

Warfarin Institute of America To Reverse an Elevated INR

A complete Guide to Healthy Eating When Takin Coumadin/ A link to where you can order this book from

Pharmacotherapy. 1996 Nov-Dec;16(6):1009-17.

Limitations of heparin have led to the development of new classes of drugs.