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Comparing the New Blood Thinners to Warfarin

Overview of the New Drugs continued...

But if blood levels rise too much with the new drugs, there is no ''antidote'' as there is with warfarin. If blood levels of warfarin rise too much, giving vitamin K brings them down, Yancy says.

With the new drugs, he says, ''there's no antidote for overshooting, unless it's fresh plasma, which has its own risks." With time, the drugs clear the body.

High blood levels of the new drugs can become an issue if a patient needs emergency surgery, Doherty says, as that would raise bleeding risk.

Comparing Pradaxa, Xarelto, Eliquis

No head-to-head comparison of the three new drugs has been made. But researchers looked at data from clinical trials for all three new drugs and did an indirect comparison.

That method has limitations, though, because the patients studied vary from trial to trial and different doses were studied.

Even so, in this comparison, published in 2012 in the Journal of the American College of Cardiology, the researchers overall found no significant differences in stroke prevention among the three drugs. The researchers did conclude that Eliquis was linked to less major bleeding, but more medical studies are needed to better pinpoint any advantages among the three drugs.

Smaller differences, such as the dosing schedules, may persuade a doctor to choose one over the other, Yancy says.

Here’s a closer look at the three new blood thinners.


The usual dose of Pradaxa is a 150-milligram tablet, taken twice a day, with or without food.

In studies comparing it to warfarin, those on the newer drug had fewer strokes, according to the FDA.

However, after Pradaxa was approved, the FDA received a large number of reports of bleeding, such as gastrointestinal and brain bleeds.

The FDA investigated, concluding in 2012 that the bleeding risks do not appear any higher than in people taking warfarin.


For stroke risk reduction, the usual dose of Xarelto is 20 milligrams once a day, taken with the evening meal. Doses can be different for other conditions.

The once-daily dose may appeal to some patients, Doherty says. It's easier to remember than multiple pills.

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