It is also important to remember that use of rivaroxaban 2.5 mg twice a day in combination with aspirin should be avoided in patients with a strong influence from cytochrome P450 (CY3A4, CYP2J2) drug interactions or with glycoprotein-p interactions among those with liver failure, bleeding diathesis, or coagulopathy, in addition to patients with a recent stroke (< 1 month), any prior hemorrhagic stroke, and estimated glomerular filtration rate < 15 mL/min (Chart 9).78,85. This evidence concerns the gene ABCB1 and hemorrhagic stroke.