Dabigatran

How it works

It is a prodrug converted to dabigatran, which directly and reversibly inhibits free and clot-bound thrombin (factor IIa), preventing conversion of fibrinogen to fibrin.

Prescribing in practice

• It is substantially renally cleared, so renal function must be assessed before and during treatment and the drug avoided or dose-adjusted in significant impairment to limit bleeding risk.
• Absorption depends on P-glycoprotein, so interactions with verapamil, dronedarone and inducers such as rifampicin are relevant, and dyspepsia is a common adverse effect.
• A specific reversal agent, idarucizumab, is available for life-threatening bleeding or emergency surgery.

Monitoring

Check renal function at baseline and at least annually, more often in the elderly or when function may decline, and review for signs of bleeding rather than routine coagulation testing.

Counselling the patient

• Swallow capsules whole and keep them in the original blister or bottle to protect from moisture.
• Report any unusual or prolonged bleeding.
• Do not miss doses, and carry an anticoagulant alert card.

Evidence & guidelines

The RE-LY trial demonstrated dabigatran was at least as effective as warfarin for stroke prevention in atrial fibrillation, supporting its NICE-recommended use.