HemoSense develops, manufactures and sells easy-to-use, handheld blood coagulation monitoring systems for use by patients and healthcare professionals in the management of warfarin medication. Warfarin is an oral anticoagulant, or blood thinning, drug given to patients to prevent potentially lethal blood clots.

Their primary product, the INRatio System, consists of a small, portable meter and disposable test strips and provides a quick and accurate measurement of a patient's blood clotting time, known as a PT/INR value. The accurate measurement of the PT/INR value is critical to ensuring the safety and effectiveness of warfarin in maintaining a patient’s blood coagulation level within a therapeutic range. HemoSense is part of Alere Health.