Pharmacology and safety of new oral anticoagulants: the challenge of bleeding persists.

New oral anticoagulants (NOACs) are increasingly replacing vitamin K antagonists and older parenteral agents in clinical practice. NOACs offer several advantages compared with standard agents, including rapid onset of action, fixed dosing, and no requirement for routine coagulation monitoring. However, like all anticoagulants, NOACs carry a risk of bleeding. Here, we discuss the pharmacology and safety of NOACs, with particular emphasis on the risks of bleeding associated with NOACs versus standard anticoagulants, and we provide an overview of current bleeding management strategies.