David A. Garcia, MD; Michael J. Schwartz, MD Anticoagulation Clinic, Warfarin therapy: University of New Mexico Health Sciences Center, Albuquerque (Dr. Garcia); Tips and tools for better control Health Services at Columbia University, New York, NY (Dr. Schwartz, retired) Monitoring patients on warfarin therapy is challenging.
[email protected] Th e tools highlighted here—from online forums and Dr. Garcia reported that he receives Web-based dosing calculators to patient education research support from, and serves as a consultant to, Bristol-Myers materials and self-monitors—can help. Squibb and serves as a consultant to Boehringer Ingelheim; Dr. Schwartz reported that he has no potential confl ict of interest relevant to this article. pproximately 4 million Americans are receiving long- PRACTICE term oral anticoagulation therapy to reduce the risk of RECOMMENDATIONS Aprimary and secondary thromboembolism.1,2 And, as › INR testing by an anti- the population ages, the number of patients on lifelong thera- coagulation management py with warfarin—the only oral anticoagulant available in the service or private clinician United States until dabigatran was approved by the US Food can be reduced to intervals of and Drug Administration late last year3—is expected to grow.4 as long as 4 weeks, but should Such patients present a challenge for family physicians. be more frequent when dos- Warfarin is notorious for having both a narrow therapeutic ing adjustments occur. B index and numerous drug and dietary interactions.5,6 To safe- › Weekly patient self-testing guard patients on warfarin therapy, frequent, and diligent, is associated with comparable monitoring is required.