What is the dose of Pradaxa (dabigatran) for pulmonary embolism (PE)?

Dosing of Dabigatran (Pradaxa) for Pulmonary Embolism

The recommended dose of dabigatran for pulmonary embolism is 150 mg taken orally twice daily after 5-10 days of parenteral anticoagulation. 1

Initial Treatment Approach

Dabigatran requires an initial course of parenteral anticoagulation before transitioning to oral therapy, unlike some other direct oral anticoagulants (DOACs). This is a critical distinction in the treatment protocol:

1. Initial parenteral anticoagulation (5-10 days):

   • Start with unfractionated heparin, low molecular weight heparin (LMWH), or fondaparinux
   • Common LMWH options include:
     • Enoxaparin 1.0 mg/kg every 12 hours or 1.5 mg/kg once daily 2
     • Tinzaparin 175 U/kg once daily 2

2. Transition to dabigatran:

   • After 5-10 days of parenteral therapy
   • Dose: 150 mg twice daily 2, 1
   • For patients with creatinine clearance (CrCl) >30 mL/min

Important Dosing Considerations

Renal Function

• CrCl >30 mL/min: 150 mg twice daily
• CrCl ≤30 mL/min or on dialysis: Dosing recommendations cannot be provided; avoid use 1
• CrCl <50 mL/min with concomitant P-gp inhibitors: Avoid coadministration 1

Administration Guidelines

• Capsules should be swallowed whole with a full glass of water
• Breaking, chewing, or emptying capsule contents increases exposure 1
• If a dose is missed, it should be taken as soon as possible on the same day if at least 6 hours before the next scheduled dose 1

Duration of Treatment

The duration of anticoagulation therapy depends on risk factors:

• Secondary PE due to transient/reversible risk factors: 3 months
• Unprovoked PE or persistent risk factors: Extended (>3 months)
• Recurrent PE: Indefinite 3

Comparison with Other DOACs

Unlike dabigatran, other DOACs have different initial dosing protocols for PE:

• Apixaban: 10 mg twice daily for 7 days, then 5 mg twice daily (no parenteral anticoagulation required) 2, 3
• Rivaroxaban: 15 mg twice daily for 21 days, then 20 mg once daily (no parenteral anticoagulation required) 2, 3
• Edoxaban: 60 mg once daily after 5-10 days of parenteral anticoagulation (similar to dabigatran) 2, 3

Special Considerations and Precautions

• Monitoring: Unlike warfarin, routine monitoring of anticoagulation effect is not required 1
• Bleeding risk: Major bleeding occurs in approximately 1.6% of patients on dabigatran compared to 1.9% on warfarin 2
• Missed doses: Do not double the dose to make up for missed doses 1
• Drug interactions: Avoid P-gp inhibitors in patients with reduced renal function 1

Clinical Evidence

The RE-COVER and RE-COVER II trials demonstrated that dabigatran was non-inferior to warfarin for treatment of PE with rates of recurrent VTE of 2.4% vs 2.1% and 2.3% vs 2.2%, respectively 2. The PEITHO-2 trial showed that early switch from heparin to dabigatran following standard clinical assessment was effective and safe in patients with intermediate-risk PE 4.

Common Pitfalls to Avoid

1. Starting dabigatran without prior parenteral anticoagulation - Unlike rivaroxaban and apixaban, dabigatran requires 5-10 days of parenteral anticoagulation first
2. Using in severe renal impairment - Avoid in patients with CrCl ≤30 mL/min
3. Improper capsule administration - Capsules must be swallowed whole
4. Drug interactions - Be cautious with P-gp inhibitors, especially in renal impairment

Remember that dabigatran is contraindicated in patients with mechanical heart valves and should be used with caution in the elderly and those with renal impairment.