WHAT TO TRY FIRST
The 2014 American Heart Association and American College of Cardiology Guidelines recommend 1 of 4 blood thinners (Coumadin, Eliquis, Pradaxa or Xarelto) to prevent strokes or dangerous blood clots for people with atrial fibrillation (not from a heart valve problem) who are at high risk of stroke because they are age 75 years or older, have had a prior stroke or mini-stroke (TIA), or are at high risk of stroke because at least 2 of the following are true: age 65-74 years, any history of congestive heart failure, hypertension, diabetes or vascular disease (prior heart attack, peripheral artery disease, or atherosclerotic plaque in aorta). You can calculate your stroke risk here.
In a systematic look at all the evidence, the Agency for Health Care Research and Quality found that Eliquis and Pradaxa are more effective than Coumadin in reducing strokes, and Eliquis may be safer (cause less bleeding) and may reduce overall chance of dying more than Coumadin. In contrast, Xarelto is not worse than Coumadin in reducing strokes or causing bleeding.
While the blood thinning from Coumadin can be reversed with Vitamin K, there is no immediate bleeding antidote for Eliquis, Pradaxa or Xarelto (but they are eliminated from the body faster than Coumadin).
The FDA-approved information for doctors says:
Patients taking Coumadin - not the other blood thinners - need regular blood tests and dose adjustments to ensure it is working safely.
WHAT ELSE TO TRY
Patients who can't take any of the recommended blood thinners are sometimes given aspirin plus clopidogrel - but the combination is not as good as Coumadin in preventing strokes and may cause more bleeding.
American College of Cardiology/American Heart Association. 2014 American Heart Association/American College of Cardiology Guideline for the Management of Patients with Atrial Fibrillation. Published December 2014.
Agency for Healthcare Research and Quality. Effective Health Care Program: Stroke Prevention in Atrial Fibrillation. Published August 2013.
FDA. Eliquis Prescribing Information. Published August 2014.
FDA. Pradaxa Prescribing Information. Published April 2014.
FDA. Xarelto Prescribing Information. Published December 2011.