Synopsis
Choose an anticoagulant from the indication, clot context, bleeding risk, organ function and patient priorities, then prescribe a defined duration with a documented review or stopping plan.
- Define the indication before the drug: venous thromboembolism, atrial fibrillation, mechanical valve, acute coronary disease and thromboprophylaxis use different agents, doses and endpoints.
- For confirmed proximal DVT or PE, NICE recommends at least 3 months of anticoagulation; review at 3 months whether the event was provoked, unprovoked, cancer associated or still supported by a persistent risk.
- Apixaban or rivaroxaban is a first-line option for most adults with DVT or PE when renal function, interactions, body context, adherence and bleeding risk permit.
Key red flags
Haemodynamic instability, syncope, severe hypoxaemia or right-heart strain with suspected PE requires an emergency reperfusion assessment rather than an ordinary outpatient anticoagulation decision.
Investigation priorities
Establish bleeding reserve and calculate a safe agent-specific dose.
Detect a condition that can change the preferred long-term anticoagulant.
Management branches
Objective imaging confirms proximal DVT or PE and there is no immediate reperfusion indication.
- Assess haemodynamics, bleeding, renal and liver function, weight, pregnancy, cancer, APS and interactions.
- Use apixaban or rivaroxaban when suitable, or give therapeutic heparin before dabigatran, edoxaban or a vitamin K antagonist pathway.
Key medicines
ApixabanFor acute DVT or PE give 10 mg orally twice daily for 7 days, then 5 mg twice daily; after 6 months, 2.5 mg twice daily may be used for extended prevention when continued treatment is chosen.
RivaroxabanFor acute DVT or PE give 15 mg orally twice daily with food for 21 days, then 20 mg once daily with food; after at least 6 months, 10 mg once daily is an extended-prevention option, with 20 mg considered when recurrence risk is high.