prescription drug box and pills of Xarelto

prescription drug box and pills of Xarelto (© Richard Villalon -

ANN ARBOR, Mich. — Patients diagnosed with blood clots or atrial fibrillation, a type of irregular heartbeat, are often prescribed medications known as anticoagulants (blood thinners) to prevent future clots. However, a dire new study reveals that the popular blood thinner Xarelto has a higher risk of triggering bleeding complications.

Researchers from the University of Michigan focused on the three most commonly used oral anticoagulants: rivaroxaban (Xarelto), apixaban (Eliquis), and warfarin. Analyzing over a decade of patient data from the Michigan Anticoagulation Quality Improvement Initiative registry, the study found that rivaroxaban was linked to a notably higher risk of bleeding than apixaban and warfarin in patients with blood clots or atrial fibrillation.

“We found the highest rates of bleeding among patients who took rivaroxaban, followed by warfarin and then apixaban,” says study first author Dr. Jordan Schaefer, a clinical associate professor of hematology at the University of Michigan Medical School, in a university release.

“We followed patients for over two years on average and were able to compare apixaban to rivaroxaban, something that has not yet been done in a randomized clinical trial. While the findings should be confirmed with randomized studies, they may have implications for providers as they select anticoagulants for their patients.”

Man reaching for prescription from medicine cabinet
(© Burlingham –

Researchers quantified the risk by estimating that for every 100 patients observed over a year, rivaroxaban would result in nearly 40 bleeding events compared to around 25 for warfarin. Although the number of bleeding events was similar for apixaban and warfarin, the latter was associated with more severe bleeds.

While the rate of blood clots was higher with apixaban than with warfarin, researchers suggest this was largely due to other thrombotic events like heart attacks. In terms of mortality, apixaban was associated with a lower death rate compared to both rivaroxaban and warfarin.

“These three medications are the most commonly prescribed anticoagulants for thrombosis and atrial fibrillation, and it is important that we continue to investigate the possible effect they carry as we attempt to best serve our patients,” notes study senior author Dr. Geoffrey Barnes, an associate professor of cardiology-internal medicine at University of Michigan Medical School.

This study underscores the need for careful consideration in prescribing anticoagulants, given the varying risks associated with different medications.

The study was presented at the 2023 American Society of Hematology’s Annual Meeting & Exposition.

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1 Comment

  1. PJ London says:

    “.. blood thinner … linked to higher risk of bleeding complications.”
    No Shit Sherlock!!