CriticalDirect thrombin inhibitor×Vitamin K antagonist anticoagulants
Updated · Methodology
Mechanism
Warfarin blocks vitamin K-dependent clotting factor synthesis; dabigatran is a direct thrombin inhibitor. The two mechanisms are additive with bleeding risk.
Symptoms
Gum bleeding, epistaxis, bruising without trauma, blood in urine or stool, menorrhagia. Severe cases include gastrointestinal or intracranial haemorrhage, gross haematuria with renal colic, spontaneous retroperitoneal haematomas. Symptoms may appear within days of co-prescription.
Management
The combination is not prescribed. Switching from warfarin to dabigatran: stop warfarin, wait for INR below 2.0, then start dabigatran. Reverse switch: start warfarin 3 days before stopping dabigatran if creatinine clearance is over 50 mL/min, 2 days if 30–50 mL/min, 1 day if below 30 mL/min.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Summary of a multi-drug list →
Medicine list: everything you take in one place →
Sources
- FDA: Pradaxa (dabigatran etexilate) prescribing information (2015)– ; DailyMed setid ba74e3cd-b06f-4145-b284-5fd6b84ff3c9
- AEMPS: Ficha técnica: Dabigatrán (nº registro 86841), sección 4.3 (2026)– AEMPS, CIMA, nº registro 86841, revisión 05/2026, sección 4.3