Pharmacology · Class
Direct oral anticoagulants (DOACs) !
Tablets or capsules that block one clotting enzyme directly: factor Xa or thrombin. No routine INR.
Updated 2026-11-01
What they are
Oral anticoagulants that bind a single clotting enzyme directly, without antithrombin: factor Xa inhibitors (the -xabans) and the direct thrombin inhibitor dabigatran.
Mechanism of action
Each drug binds its target enzyme directly. Rivaroxaban blocks free factor Xa and the Xa inside the prothrombinase complex, which cuts thrombin production; dabigatran blocks free and clot-bound thrombin. Either way less fibrin forms and thrombin-driven platelet aggregation falls.
Target: Factor Xa (xabans) or thrombin (dabigatran)
Drugs in this class
- RivaroxabanAn oral anticoagulant that blocks factor Xa directly. It needs no routine INR, and andexanet alfa can reverse it.Coagulation factor Xa
- DabigatranAn oral anticoagulant that blocks thrombin directly. It is cleared mainly by the kidneys and has its own antidote…Thrombin (coagulation factor IIa)
- ApixabanAn oral anticoagulant that blocks clotting factor Xa directly. Used in atrial fibrillation and venous thrombosis, with…Coagulation factor Xa
- EdoxabanA once-daily oral factor Xa inhibitor for atrial fibrillation and venous thrombosis. Half of it leaves through the…Coagulation factor Xa
Others in the class
- apixaban
- edoxaban
Test yourself
Think of the answer, then tap the question to see it.
What separates a direct anticoagulant from heparin?
A direct anticoagulant binds factor Xa or thrombin itself. Heparin needs antithrombin as a go-between.
What is the specific reversal agent for dabigatran, and for rivaroxaban?
Dabigatran: idarucizumab, an antibody fragment that binds it. Rivaroxaban: andexanet alfa, an inactive modified factor Xa that binds and holds the drug.
In which two settings is warfarin preferred over a DOAC?
Mechanical heart valves and triple-positive antiphospholipid syndrome, where DOACs led to more clots.
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: DailyMed - RIVAROXABAN tablet (DailyMed (U.S. National Library of Medicine), 2026); DailyMed - DABIGATRAN- dabigatran etexilate capsule (DailyMed (U.S. National Library of Medicine), 2026); eEML - Electronic Essential Medicines List (World Health Organization, 2025).
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Representative model, for educational purposes only.