Factor Xa Inhibitors
Examples
- Rivaroxaban
- Apixaban
- Edoxaban
- Fondaparinux
Indications
- Prophylaxis of thromboembolism following surgery
- Initial and continued treatment of DVT/PE
- Prophylaxis of thromboembolic events
- Treatment of non-ST and ST-elevated myocardial infarction/unstable angina
- Fondaparinux can also be used in the treatment of Heparin Induced Thrombocytopenia ( unlicensed )
Contraindications
Contra-indications:
- Active bleeding
- Bacterial Endocarditis (fondaparinux only)
- Recent surgery
- Recent brain or spinal cord injury
- Vascular aneurysms
- GI ulceration
- Hepatic Disease
- Oesophageal varices
- Pregnancy and breastfeeding
- Liver and renal impairment
- Elderly patients
Mechanism
Factor Xa amplifies coagulation by converting prothrombin to thrombin in response to injury. Direct inhibitors (rivaroxaban, apixaban) block the active site of the factor Xa molecule.
Fondaparinux is an indirect inhibitor and works by enhancing the ability of antithrombin to neutralise Factor Xa.
Fondaparinux is an indirect inhibitor and works by enhancing the ability of antithrombin to neutralise Factor Xa.
Administration
- Oral
- Subcutaneous injection (fondaparinux)
- Intravenous injection (fondaparinux)
Adverse Reactions
- Anaemia
- Bleeding
- Purpura
- Haemorrhage
- Epistaxis (edoxaban)
- GI upset (rivaroxaban)
Interactions
Use with NSAIDs, SSRIs and anti-platelet drugs increases the risks of bleeding
Education
Inform patients of interactions with commonly prescribed/OTC medications.
Pharmacokinetics
Nil relevant.
