At least 18 deaths and 1,500 injuries from major bleeding have occurred when the recalled INRatio Monitor gave inaccurately low readings, resulting in patients overdosing on blood-thinning drugs.
What is INRatio?
Alere Inc. manufactures INRatio® and INRatio2®, a handheld device that tells patients what dose of the blood-thinner warfarin they must take every day.
How Does INRatio Work?
INRatio analyzes a drop of blood on a test strip to measure blood-clotting times — also known as Prothombin Time (PT) and International Normalized Ratio (INR). Patients on warfarin must frequently check their PT/INR to adjust the dose of warfarin.
Alere INRatio Recall
July 2016 — Alere has issued a Class I recall for the entire INRatio System, including monitors and test strips, because they may produce inaccurately low readings.
In December 2014, Alere issued a Class I recall for INRatio Test Strips. The company reported receiving 18,924 complaints about low readings since 2013, including three deaths.
False Readings and Major Bleeding
Erroneously low INR readings can result in a patient taking too much warfarin and experiencing “major or fatal bleeding,” according to the FDA. The FDA received 1,451 injury reports from 2002 to 2015, including 18 deaths in 2014 and 2015.
Complaints About Inaccurate Readings Ignored
Problems with inaccurate readings have been known for over a decade. The original manufacturer, HemoSense, received warnings from the FDA in 2005 and 2006 for failing to investigate complaints about erroneous readings. Even so, the INRatio devices were used in clinical trials comparing Xarelto to warfarin.