What is the recommended dose of Dalteparin (Fragmin) for the treatment of pulmonary embolism?

Dalteparin Dosing for Pulmonary Embolism Treatment

For acute pulmonary embolism treatment, administer dalteparin 200 IU/kg subcutaneously once daily for the first month, then reduce to 150 IU/kg once daily for extended therapy (months 2-6), particularly in cancer patients where dalteparin demonstrates superior efficacy compared to oral anticoagulants. 1, 2

Initial Treatment Phase (Days 1-30)

• Dose: 200 IU/kg subcutaneously once daily 1, 2
• Minimum duration: 5-7 days before transitioning to oral anticoagulation if warfarin is chosen 1
• Alternative dosing: 100 IU/kg every 12 hours is an option, though once-daily dosing is the FDA-approved and most studied regimen for cancer-associated PE 1

The NCCN assigns a Category 1 recommendation to dalteparin for PE treatment, reflecting the highest quality evidence from the landmark CLOT trial, which demonstrated 52% reduction in recurrent VTE (8.0% vs 15.8%, HR 0.48, P=0.002) compared to warfarin without increasing bleeding risk 1, 2

Extended Treatment Phase (Months 2-6)

• Dose reduction: After 1 month, decrease to 150 IU/kg subcutaneously once daily 1, 2
• Duration: Continue for minimum 6 months total; in cancer patients, extend as long as active malignancy persists 1
• Alternative approach: ESMO guidelines support using 75-80% of initial LMWH dose for extended therapy 1

Special Population Adjustments

Renal Impairment

• Creatinine clearance <30 mL/min: Monitor peak anti-Xa levels (dalteparin may be sufficiently cleared, but monitoring is essential) 1
• Dalteparin has advantages over enoxaparin in severe renal dysfunction, as available data suggest adequate clearance, though anti-Xa monitoring remains recommended 1

Obesity (BMI ≥40 kg/m²)

• No specific dose adjustment guidelines exist for dalteparin in extreme obesity 1
• Consider anti-Xa level monitoring to ensure therapeutic anticoagulation 1

Low Body Weight (<50 kg)

• Use weight-based dosing as standard; institutional protocols should address this population 1

Cancer Patients: Critical Considerations

Dalteparin is the only LMWH with FDA approval specifically for extended treatment of cancer-associated VTE and is supported by the highest quality evidence. 1, 2

• Cancer patients have 3-fold higher VTE recurrence risk on warfarin compared to LMWH 2
• Continue anticoagulation indefinitely while cancer remains active 1
• The CLOT trial specifically enrolled cancer patients with acute symptomatic PE and demonstrated clear superiority of dalteparin over oral anticoagulation 2

Transition to Oral Anticoagulation (If Chosen)

If transitioning to warfarin instead of continuing dalteparin:

• Overlap dalteparin with warfarin for minimum 5-7 days 1
• Continue dalteparin until INR is 2-3 for 2 consecutive days 1
• Start warfarin on day 1 of dalteparin therapy 1

However, in cancer patients, continuing dalteparin monotherapy is superior to warfarin and represents the preferred strategy. 1, 2

Monitoring Requirements

• Platelet count: Every 2-3 days from day 4 to day 14 to screen for heparin-induced thrombocytopenia 1
• Anti-Xa levels: Not routinely required, but indicated for severe renal impairment (CrCl <30 mL/min), extreme obesity, or pregnancy 1
• Hemoglobin/hematocrit: Monitor for occult bleeding 1

Common Pitfalls to Avoid

• Do not use fixed dosing: Always calculate weight-based dosing (200 IU/kg, not a fixed 10,000 IU dose for PE) 1, 3
• Do not forget dose reduction: After month 1, reduce to 150 IU/kg for extended therapy 1, 2
• Do not use warfarin as first-line in cancer: Dalteparin demonstrates clear superiority with 52% reduction in recurrent VTE 1, 2
• Do not stop prematurely: Cancer patients require minimum 6 months, often indefinite therapy 1

Outpatient Management Feasibility

Selected hemodynamically stable PE patients can be managed as outpatients with dalteparin 200 IU/kg once daily, with recurrence rates of 5.6% and major bleeding rates of 1.9% in prospective studies 4. Exclude patients with hypoxia requiring oxygen, hemodynamic instability, severe pain requiring parenteral analgesia, or high bleeding risk 4.