Warfarin therapeutic monitoring: is 70% time in the therapeutic range the best we can do?

WHAT IS KNOWN AND OBJECTIVE

Warfarin, an oral anticoagulant, which has been in clinical use for over sixty years, remains a challenge for clinicians to utilize, given the multiplicity of items which can limit its efficacy. Our objective is to review the evidence and comment on whether INR control can be better than has been currently reported in various studies.

COMMENT

The duration of time a patient's international normalized ratio (INR) is maintained within the therapeutic range (time in the therapeutic range, TTR) for his or her particular indication for the drug impacts the effectiveness and safety of warfarin therapy. Maintaining a therapeutic INR while on warfarin is difficult, and numerous studies employing various strategies confirm the challenge, but not the impossibility of achieving a TTR above 70%.

WHAT IS NEW AND CONCLUSION

Maintaining a therapeutic INR requires a dedicated multi-faceted approach. With diligence, skill and various therapeutic strategies, a TTR >70% can be achieved.