Can Lovenox (enoxaparin) be given to a patient already on Eliquis (apixaban)?

Administering Lovenox (Enoxaparin) in Patients on Eliquis (Apixaban)

Lovenox (enoxaparin) should not be administered to patients already on Eliquis (apixaban) as this combination significantly increases bleeding risk without providing additional thrombotic protection. 1

Pharmacological Considerations

Apixaban (Eliquis) is a direct Factor Xa inhibitor with the following characteristics:

• Half-life of approximately 12 hours
• 27% renal excretion, 73% biliary and intestinal excretion
• P-glycoprotein substrate with CYP3A4 metabolism 1

Enoxaparin (Lovenox) is a low molecular weight heparin that:

• Inhibits coagulation factors XIa, IXa, Xa, and IIa (thrombin)
• Has a half-life of 4-7 hours
• Has 80% renal excretion 2, 3

Clinical Decision Algorithm

1. For patients on Eliquis requiring surgery/procedures:

   • Follow appropriate discontinuation protocols (3 days before procedure for normal renal function)
   • Do NOT bridge with enoxaparin during this period 1

2. For patients with acute thrombotic events already on Eliquis:

   • Do not add enoxaparin
   • Consider switching anticoagulation strategy completely if current regimen is ineffective
   • Consult hematology for specialized guidance

3. For patients transitioning between anticoagulants:

   • Complete discontinuation of one agent before starting the other
   • For switching from apixaban to enoxaparin: Discontinue apixaban and start enoxaparin at the time the next dose of apixaban would have been due
   • For switching from enoxaparin to apixaban: Start apixaban 0-2 hours before the next scheduled dose of enoxaparin 1

Evidence Against Concurrent Use

The 2024 ACC/AHA guidelines for atrial fibrillation management do not recommend concurrent use of multiple anticoagulants 1. Combining anticoagulants with different mechanisms of action significantly increases bleeding risk without providing additional thrombotic protection.

The French Working Group on Perioperative Hemostasis (GIHP) explicitly states that there is no need for heparin bridging when interrupting direct oral anticoagulants like apixaban except in very high thrombotic risk situations 1.

Special Considerations

High Bleeding Risk Scenarios

Patients with the following characteristics are at particularly high risk if given both agents:

• Age ≥75 years
• Renal impairment (CrCl <50 mL/min)
• Low body weight (<60 kg)
• History of bleeding disorders
• Concurrent antiplatelet therapy 2

Misconceptions About "Bridging"

A common clinical error is attempting to "bridge" with enoxaparin when a patient on apixaban needs surgery. This practice:

• Is not supported by guidelines
• Increases bleeding risk
• Provides no additional thrombotic protection 1

Rare Exceptions

In very specific clinical scenarios involving patients at extremely high thrombotic risk (e.g., recent stent placement with proximal LAD involvement), bridging therapy might be considered, but this should involve IV glycoprotein inhibitors (tirofiban or eptifibatide) rather than enoxaparin 1.

Conclusion

The concurrent administration of enoxaparin and apixaban creates an unnecessarily high bleeding risk without providing additional thrombotic protection and should be avoided in clinical practice.