Fragmin (Dalteparin) Dosing for DVT Treatment and Prophylaxis
For DVT treatment, use dalteparin 200 IU/kg subcutaneously once daily for the first month, then reduce to 150 IU/kg once daily for extended therapy; for DVT prophylaxis, use 5,000 IU subcutaneously once daily. 1
Treatment Dosing (Therapeutic Anticoagulation)
Initial/Acute Phase
- 200 IU/kg subcutaneously once daily for the first 30 days 1
- Alternative regimen: 100 IU/kg subcutaneously every 12 hours 2
- Minimum duration: 5-10 days for initial treatment 3, 2
Extended/Long-Term Treatment
After the first month, reduce to 150 IU/kg subcutaneously once daily 1. This dose reduction is based on the landmark CLOT study and is specifically recommended for cancer-associated thrombosis, though the principle applies broadly 4, 1.
Total treatment duration:
- Minimum 3-6 months for most patients 4, 2
- Extended therapy (potentially indefinite) for cancer patients while malignancy is active or during chemotherapy 4, 3, 2
Prophylaxis Dosing
5,000 IU subcutaneously once daily 1, 5, 6, 2
This standard prophylactic dose applies to:
- Hospitalized medical patients at high thromboembolic risk
- Surgical patients (continue throughout hospitalization or until ambulatory) 5, 6
- Duration: Until hospital discharge or full ambulation 6, 2
Renal Impairment Adjustments
Severe Renal Insufficiency (CrCl <30 mL/min)
Dalteparin has a significant safety advantage over enoxaparin in renal impairment and does not require routine dose adjustment 1. The evidence shows:
- Prophylactic dosing (5,000 IU daily): No dose adjustment needed. Studies demonstrate no bioaccumulation with peak anti-Xa levels of 0.29-0.34 IU/mL 1, 7
- Therapeutic dosing: For cancer patients with CrCl <30 mL/min receiving extended treatment, monitor peak anti-Xa levels 4-6 hours after dosing (after 3-4 doses) to achieve target range of 0.5-1.5 IU/mL 1
This contrasts sharply with enoxaparin, which requires dose reduction to 1 mg/kg once daily for treatment and 30 mg daily for prophylaxis in severe renal impairment due to 2-3 fold increased bleeding risk 1.
Moderate Renal Impairment (CrCl 30-50 mL/min)
Exercise caution but no specific dose adjustment is mandated for dalteparin 1. Consider monitoring anti-Xa levels in high-risk situations.
Key Safety Data
A multicenter study of 138 critically ill patients with severe renal impairment (mean CrCl 18.9 mL/min) receiving prophylactic dalteparin 5,000 IU daily showed zero cases of bioaccumulation (0%; 95% CI: 0%-3.0%) with median trough anti-Xa levels remaining undetectable 7.
Special Populations
Obesity (>90 kg)
- Continue weight-based dosing without capping at 200 IU/kg daily (up to 33,000 IU studied) 8
- Recent prospective data in patients >90 kg (median 107.5 kg) showed acceptable bleeding rates (5.3% at 30 days) and low recurrence (1.2%) 8
- Monitor trough anti-Xa levels if concerned; levels >0.6 IU/mL associated with increased bleeding 8
Elderly Patients (≥70 years)
- Avoid tinzaparin in patients ≥70 years with renal insufficiency due to increased mortality (11.2% vs 6.3% with UFH, p=0.049) 1
- Dalteparin remains safe; no dose adjustment needed for age alone 9
Low Body Weight (<50 kg)
Use caution with weight-based dosing; consider monitoring anti-Xa levels 1.
Clinical Pearls and Pitfalls
Common pitfalls to avoid:
- Do not confuse dalteparin with enoxaparin dosing – they are not interchangeable despite being in the same drug class 1
- Do not automatically reduce LMWH doses in renal impairment – dalteparin specifically does not require adjustment unlike enoxaparin 1
- Do not forget the dose reduction after 1 month for extended therapy (200→150 IU/kg) 1
Monitoring considerations:
- Routine anti-Xa monitoring is not required for most patients 1
- Monitor anti-Xa levels only in: severe renal impairment (CrCl <30 mL/min) on therapeutic doses, extremes of body weight, or unexplained bleeding 1
- Measure 4-6 hours post-dose after 3-4 doses have been administered 1
Advantages of dalteparin over alternatives: