Choosing the correct dose of an anticoagulant is important to ensure that the patient receives the benefits in terms of reduction of thrombo-embolic events whilst minimising the risk of adverse bleeding events. For many patients the direct acting oral anticoagulants (DOACs) are now an alternative to treatment with a vitamin K antagonist (usually warfarin).

The purpose of this paper is to explain the background to dosing decisions for DOACs in patients with impaired renal function. The paper focuses on the use of DOACs in patients with atrial fibrillation and provides cases from clinical practice as examples.  It is intended as a practice aid, not national guidance, and is particularly suitable for new or less experienced practitioners working in primary care.

Since the initial publication of this paper the MHRA has issued advice for healthcare professionals which states that when selecting the dose of DOAC the creatinine clearance (CrCl) should be calculated to inform dosing decisions.