Dabigatran, rivaroxaban, and apixaban are the new oral anticoagulants (NOAC) 
which have been investigated in patients with atrial fibrillation (AF) for 
primary and secondary prevention of stroke and thromboembolism. In these trials 
NOAC had a similar efficacy and safety profile compared to traditional 
vitamin-K-antagonists such as warfarin. We advise caution in the use of NOAC in 
patients with stroke or cerebral hemorrhage because of the following reasons: 1) 
Patients with cerebral bleeding were excluded from the trials. 2) Stroke within 
14 days and severe stroke within 6 months before screening were exclusion 
criteria in the trials investigating dabigatran and rivaroxaban. 3) There is no 
antidote for reversal and no reliable laboratory monitoring of the anticoagulant 
effect for emergency situations. 4) NOAC are either substrates of the 
P-glycoprotein (P-gp) or are metabolized by the cytochrome P450 (CYP) system, or 
both. Drug-drug interactions between NOAC and P-gp and CYP-affecting drugs are 
largely unknown. 5) Long-term effects of thrombin generation inhibition on the 
occurrence of infections, malignancies, dementia, and other diseases are 
unknown. Based on these considerations it is our opinion that studies of NOAC in 
patients with stroke compared with other prevention strategies, as well as more 
post marketing surveillance data, are required.