When is a dose of 60 mg of enoxaparin (low molecular weight heparin) given?

When to Give 60 mg of Enoxaparin

Enoxaparin 60 mg subcutaneously is given twice daily for outpatient treatment of acute coronary syndromes in patients weighing ≥65 kg, and once daily for VTE prophylaxis in obese patients (particularly those with BMI >40 kg/m² or weight ≥150 kg). 1

Clinical Contexts for 60 mg Dosing

Acute Coronary Syndromes - Outpatient Treatment

• For patients with unstable angina/NSTEMI weighing ≥65 kg in the outpatient setting, give enoxaparin 60 mg subcutaneously twice daily 1
• Patients weighing <65 kg should receive 40 mg subcutaneously twice daily instead 1
• This dosing was validated in the TIMI 11B trial, which demonstrated reduced death, MI, and urgent revascularization compared to placebo (OR 0.83,95% CI 0.69-1.00, p=0.048) 1

VTE Prophylaxis in Obese Patients

• For obese patients requiring VTE prophylaxis, particularly those with BMI ≥40 kg/m² or weight ≥150 kg, give enoxaparin 60 mg subcutaneously once daily 1, 2
• This higher dose achieves target prophylactic anti-Xa levels (0.2-0.5 IU/mL) in obese patients where standard 40 mg dosing is insufficient 1, 3, 4
• The 2022 AHA/ACC/HFSA Heart Failure Guidelines specifically recommend 60 mg once daily for obese patients hospitalized with heart failure to achieve adequate thromboprophylaxis 1

Weight-Based Prophylaxis in Morbidly Obese Surgical/ICU Patients

• For morbidly obese patients (BMI ≥35 kg/m² or weight ≥150 kg) in surgical ICU settings, enoxaparin 60 mg twice daily may be appropriate as part of a weight-based protocol (0.5 mg/kg every 12 hours) 2, 3
• This dosing achieves mean anti-Xa levels of 0.34 IU/mL (range 0.20-0.59), within the prophylactic target range 3
• Studies show this regimen reduces VTE rates below expected levels without increased bleeding complications 3, 5

Key Dosing Algorithm

Step 1: Identify the Clinical Indication

• Acute coronary syndrome (outpatient treatment) → proceed to Step 2
• VTE prophylaxis in hospitalized patient → proceed to Step 3

Step 2: For ACS Outpatient Treatment

• Weight ≥65 kg → 60 mg subcutaneously twice daily 1
• Weight <65 kg → 40 mg subcutaneously twice daily 1

Step 3: For VTE Prophylaxis

• BMI ≥40 kg/m² or weight ≥150 kg → 60 mg subcutaneously once daily 1, 2
• BMI 35-40 kg/m² in surgical/ICU setting → Consider 60 mg twice daily (0.5 mg/kg q12h protocol) 2, 3
• Standard weight/BMI → 40 mg once daily 1, 2

Important Caveats and Pitfalls

Renal Function Considerations

• Do not use 60 mg dosing in patients with severe renal impairment (CrCl <30 mL/min) 1
• For CrCl <30 mL/min, reduce to 30 mg once daily for prophylaxis or 1 mg/kg once daily for treatment 1
• Enoxaparin accumulation occurs with renal dysfunction, increasing bleeding risk 2-3 fold 1

Age-Related Adjustments

• For patients ≥75 years receiving enoxaparin for STEMI with fibrinolysis, do not use 60 mg dosing 1, 6
• Instead, use 0.75 mg/kg subcutaneously every 12 hours without IV bolus 1, 6

Monitoring in Obesity

• Consider monitoring peak anti-Xa levels (4-6 hours post-dose) in morbidly obese patients to ensure levels are within prophylactic range (0.2-0.5 IU/mL) 1, 2, 3
• However, routine monitoring is not necessary if using established weight-based protocols 5

Common Errors to Avoid

• Do not give 60 mg twice daily for standard VTE prophylaxis in non-obese patients - this leads to supratherapeutic levels and increased bleeding risk 7, 8
• Do not use fixed 60 mg dosing for therapeutic anticoagulation - therapeutic dosing should be 1 mg/kg every 12 hours (or 1.5 mg/kg once daily) 1
• Avoid switching between enoxaparin and unfractionated heparin - this increases bleeding risk 1, 6
• Do not administer within 8-12 hours of neuraxial anesthesia to prevent spinal hematoma 2, 6