|
DOAC |
VKA |
Medicine |
Dabigatran |
Rivaroxaban |
Apixaban |
Warfarin |
Target |
Thrombin
(factor IIa) |
Factor Xa |
Vitamin K-dependent clotting (or coagulation) factors |
Half-life |
12 – 14 hours |
9 – 13 hours |
8 – 11 hours |
20 – 60 hours |
Onset of action |
2 hours |
2.5 – 4 hours |
3 hours |
Days |
Key monitoring requirements |
Renal function monitoring
(at least annually; more frequent if impaired at baseline) |
INR monitoring
(regular and ongoing) |
Funding status |
Fully funded |
Not funded |
Fully funded |
Tablet strengths available* |
75 mg
110 mg
150 mg |
10 mg
15 mg
20 mg |
2.5 mg
5 mg |
1 mg
2 mg
3 mg
5 mg |
Usual dosing frequency |
Twice day
(N.B. Once daily when used for VTE prophylaxis following surgery) |
Once daily |
Twice day |
Once daily |
Reversal agent |
Available
(idarucizumab) |
Unavailable in New Zealand
(options are available overseas) |
Available
(vitamin K, prothrombinex) |
Key interactions |
- P-gp inhibitors† (increases DOAC concentration)
- P-gp inducers** (significantly decrease DOAC concentration)
- Antacids
|
- Strong CYP3A4 inhibitor + combined P-gp inhibitor, e.g. carbamazepine, rifampin, St John’s wort (significantly increase DOAC concentration)
- Moderate CYP3A4 inhibitor + combined P-gp inhibitor, e.g. clarithromycin, diltiazem (moderately increase DOAC concentration)
- Strong CYP3A4 inducer, e.g. phenytoin (significantly decrease DOAC concentration)
- P-gp inducers** (significantly decrease DOAC concentration)
|
- Numerous medicine interactions, e.g. erythromycin and other antibiotics, antifungals, amiodarone, NSAIDs; see NZF interaction checker for a comprehensive list
- Food interactions; particularly vitamin K rich foods, e.g. avocados, broccoli, leafy green vegetables such as spinach
|
Indications
(see NZF for indication-specific dosing regimens) |
All DOACs:
- Prevention of stroke and systemic embolism in non-valvular atrial fibrillation
- Treatment of deep-vein thrombosis and pulmonary embolism
- Prevention of recurrent deep-vein thrombosis or pulmonary embolism
- Prevention of venous thromboembolism following major joint surgery, e.g. hip, knee
|
Warfarin:
- Prevention and treatment of venous thrombosis and pulmonary embolism
- Prevention of stroke following myocardial infarction in patients with increased embolic risk
- Prevention of thromboembolism in patients with atrial fibrillation
- Prevention of thromboembolism in patients with prosthetic heart valves
|
Additional indication for rivaroxaban only:
Prophylaxis of cardiovascular events in patients with coronary artery disease or peripheral artery disease (in combination with aspirin) |
Contraindications‡ or insufficient evidence to support use in primary care
(see NZF for cautions)
N.B. See Figure 1 in the full article for further information on use in patients with renal dysfunction |
All oral anticoagulants:
- Active serious bleeding
- Certain bleeding-associated co-morbidities, e.g. severe thrombocytopenia or severe anaemia
- History of recent high-risk bleeding event, e.g. intracranial haemorrhage (N.B. Patients with recent intracranial haemorrhage may still benefit from oral anticoagulant use, however, these decisions should be made in secondary care following neuroimaging)
- Pregnancy (see: "Anticoagulation during pregnancy" section in the full article)
|
All DOACs:
- Mechanical heart valves
- Moderate-to-severe mitral stenosis
- Severe liver disease
|
Warfarin:
Usually avoided in primary care for patients with severe renal impairment but may be considered under secondary care guidance, if required |
Dabigatran:
CrCl < 30 mL/min |
Rivaroxaban:
CrCl < 15 mL/min |
Apixaban:
CrCl < 25 mL/min (N.B. Use may still be considered under secondary care guidance if CrCl 15 – 24 mL/min) |
