What is the full dose of Lovenox (enoxaparin) for pulmonary embolism?

Enoxaparin Dosing for Pulmonary Embolism

The full therapeutic dose of enoxaparin (Lovenox) for pulmonary embolism is 1.0 mg/kg subcutaneously every 12 hours or 1.5 mg/kg subcutaneously once daily. 1

Dosing Regimens

• Twice-daily regimen: 1.0 mg/kg subcutaneously every 12 hours
• Once-daily regimen: 1.5 mg/kg subcutaneously once daily

Duration of Treatment

• Initial parenteral anticoagulation should be continued for at least 5 days
• Overlap with oral anticoagulant (vitamin K antagonist) until INR has been 2.0-3.0 for two consecutive days 1

Special Considerations

Renal Function

• For patients with severe renal impairment (creatinine clearance <30 mL/min):
  • Consider unfractionated heparin instead
  • If enoxaparin must be used, monitor anti-Xa levels 1

Obesity

• For severely obese patients:
  • Consider unfractionated heparin for more predictable dosing
  • If using enoxaparin, consider anti-Xa monitoring 1

Monitoring

• Routine monitoring of anti-Xa levels is not required in most patients
• Consider monitoring in:
  • Severe renal impairment
  • Pregnancy
  • Extreme body weight
• Target anti-Xa range:
  • 0.6-1.0 IU/mL for twice-daily administration
  • 1.0-2.0 IU/mL for once-daily administration 1
• Platelet count should be monitored due to risk of heparin-induced thrombocytopenia 1

Transitioning to Long-term Anticoagulation

• Start oral anticoagulant (warfarin or DOAC) as soon as possible, preferably on the same day as initial parenteral anticoagulation
• For warfarin:
  • Continue enoxaparin until INR is 2.0-3.0 for two consecutive days
  • Target INR: 2.0-3.0 1
• For DOACs:
  • When switching from enoxaparin to a DOAC, administer the DOAC 0-2 hours before the next scheduled enoxaparin dose 2

Clinical Evidence

The efficacy and safety of both dosing regimens (1.0 mg/kg twice daily and 1.5 mg/kg once daily) have been demonstrated in clinical trials. A randomized study of 900 patients with venous thromboembolism (including 32% with confirmed PE) showed equivalent efficacy between both enoxaparin regimens and unfractionated heparin 3.

However, some evidence suggests that the twice-daily regimen may be preferable in certain high-risk populations. A small study in cancer patients found a higher incidence of recurrent PE in the once-daily group compared to the twice-daily group (4 vs. 2 events) 4.

Pitfalls to Avoid

• Failing to adjust dose in severe renal impairment
• Inadequate duration of overlap when transitioning to warfarin
• Not monitoring platelet counts for heparin-induced thrombocytopenia
• Using enoxaparin in patients who should receive unfractionated heparin (e.g., those requiring thrombolysis or with severe renal impairment)

Remember that enoxaparin is preferred over unfractionated heparin for most patients with PE due to lower risk of major bleeding and heparin-induced thrombocytopenia, except in cases requiring thrombolysis or in patients with severe renal impairment 1.