Enoxaparin Dosage for DVT Prophylaxis
The standard recommended dosage of enoxaparin for DVT prophylaxis is 40 mg subcutaneously once daily for most adult patients. 1
Standard Dosing Recommendations
- Enoxaparin 40 mg subcutaneously once daily is the standard prophylactic dose for medical and surgical patients 2, 1
- Treatment should continue for the duration of hospitalization or until the patient is fully ambulatory 1
- For surgical patients, prophylaxis should continue for at least 7-10 days post-procedure 1
Special Population Dosing Adjustments
Renal Impairment
- For patients with severe renal insufficiency (creatinine clearance <30 mL/min), reduce the dose to 30 mg subcutaneously once daily 3, 1, 4
- Renal clearance of enoxaparin is reduced by 31% in moderate renal impairment (30-60 mL/min) and 44% in severe renal impairment (<30 mL/min) 3, 4
Obesity
- For patients with obesity (BMI >30 kg/m²), consider intermediate doses of 40 mg subcutaneously every 12 hours or weight-based dosing of 0.5 mg/kg subcutaneously every 12 hours 2, 1, 5
- Standard fixed dosing may be inadequate in morbidly obese patients 5, 6
- A study of morbidly obese patients showed that weight-based dosing at 0.5 mg/kg once daily resulted in appropriate anti-Xa levels without excessive anticoagulation 5
Pregnancy
- For pregnant women with class III obesity requiring thromboprophylaxis, intermediate doses of enoxaparin (0.5 mg/kg subcutaneously every 12 hours) are suggested 3
Administration Timing Considerations
- For surgical patients, initiate enoxaparin 2-4 hours preoperatively or 10-12 hours preoperatively when neuraxial anesthesia is planned 2, 1
- Avoid administration within 10-12 hours before neuraxial anesthesia to reduce the risk of spinal hematoma 1
- For prophylactic doses after neuraxial anesthesia, enoxaparin may be started as early as 4 hours after catheter removal but not earlier than 12 hours after the block was performed 3
Monitoring Recommendations
- Routine anti-Xa monitoring is not required for most patients receiving prophylactic doses 4
- For patients with severe renal impairment on prolonged therapy, consider monitoring anti-Xa levels with a target range of 0.5-1.5 IU/mL 3
- Anti-Xa levels should be measured 4-6 hours after dosing, after the patient has received 3-4 doses 3
Common Pitfalls and Caveats
- Failure to adjust dosing in renal impairment can lead to drug accumulation and increased bleeding risk 1, 4
- Standard fixed dosing may be inadequate in obese patients, potentially leading to treatment failure 5, 6
- Concomitant use with other antiplatelet or anticoagulant medications increases bleeding risk 1
- Timing of administration relative to neuraxial procedures is critical to prevent spinal hematoma 3, 1