Thromboprophylaxis - LMWH dose adjustment in extremes of weight and renal impairment

The following table provides recommended doses of enoxaparin for thromboprophylaxis including dose adjustments for extremes of body weight and renal impairment. Each patient should be considered on an individual basis for bleeding and VTE risk and discussed as necessary.

Due to limited clinical evidence for prophylactic LWMH in extremes of body weight and renal impairment, all doses recommended are ‘off-label’

For patients with an acute kidney injury (AKI), ensure the renal function is reviewed regularly and adjust enoxaparin dose as recovery of renal function occurs.

Renal function in this guidance is measured as creatinine clearance (CrCl). CrCl can be calculated using MDCalc’s Cockcroft-Gault Online Calculator available here: https://www.mdcalc.com/calc/43/creatinine-clearance-cockcroft-gault-equation

Table 1: Enoxaparin dosing table for thromboprophylaxis

 

Weight (kg)

 Enoxaparin subcutaneous dose
Dosage in CrCl ≥30ml/min

Renal Adjusted Dose

CrCl <30ml/min (including intermittent HD and CVVHD)
<50kg 20mg ONCE daily 20mg ONCE daily
50 – 100kg 40mg ONCE daily 20mg ONCE daily
101 – 150kg 40mg TWICE daily 40mg ONCE daily
>150kg

60mg TWICE daily*

Seek haematology advice*

*Monitoring of LMWH assay (Anti-Xa) is recommended only for patients with a body weight >150kg.

LMWH assay monitoring (Anti-Xa)

  • LMWH assay sampling is time dependent. The peak level sampling must be taken 3 to 4 hours after 3 days of LMWH has been administered. Monitoring of LMWH assay (Anti-Xa) is recommended only for patients with a body weight >150kg.
  • The target peak range for thromboprophylaxis is 0.1 – 0.4 units/ml. If level is within the appropriate range no further sampling is required unless there are any signs of bleeding or bruising.

 

Guideline reviewed February 2026
Page updated April 2026



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