Drugmaker Bristol-Myers Squibb has initiated a voluntary recall of a single lot of 5 mg tablets of warfarin sodium (Coumadin) because the tablets have been found to have a higher potency than expected. The lot number of warfarin affected by the recall is 9H49374A, with an expiration date of Sept. 30, 2012. Officials at the U.S. Food and Drug Administration recommend that patients in possession of these warfarin tablets should not stop taking them, but should consult their pharmacist. If the...