• Mechanism of Action
    • Binds to and activates antithrombin III, which as a heparin-ATIII complex inactivates factor Xa
    • Pharmacology
    • More potent (2-4x) than unfractionated heparin due to higher activation of antithrombin III
    • Smaller molecules are able to bind primarily to factor Xa, with little effect on IIa
    • Better bioavailability and more predictable response than heparin
    • Effective half-life is 4 hours.
    • Reversed with protamine sulfate, though less effectively than with unfractionated heparin)

Clinical Use

    • Indications
    • Prevention of venous thromboembolism (DVT / PE)
    • Treatment of venous thromboembolism (DVT / PE)
    • ST elevation myocardial infarction (STEMI)
    • Bridging anticoagulation for initiation / withholding of warfarin
    • Prevention of thrombosis during haemodialysis
    • Acute limb ischaemia (unfractionated heparin)
    • Adverse Effects
    • Haemorrhage
    • Hypersensitivity
    • Elevated LFTs
    • Thrombocytopaenia (less commonly than heparin)
    • Monitoring
    • Not monitored in most cases, though anti-factor Xa levels may be taken.
Want more info like this?
  • Your electronic clinical medicine handbook
  • Guides to help pass your exams
  • Tools every medical student needs
  • Quick diagrams to have the answers, fast
  • Quizzes to test your knowledge