ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Low Molecular Weight Heparin — VTE Prophylaxis Pregnancy: Safe — LMWH of choice in pregnancy for VTE prevention and treatment

Enoxaparin (Burns — VTE Prophylaxis)

Brand names: Clexane

Adult dose

Dose: 40 mg SC once daily (prophylaxis); treatment dose: 1 mg/kg every 12 hours or 1.5 mg/kg once daily
Route: Subcutaneous
Frequency: Once daily (prophylaxis); twice daily (treatment)
Max: 180 mg/day (treatment)
Major burns patients at very high VTE risk — immobility, hypercoagulable state, central catheters. Anti-Xa monitoring essential in burns as pharmacokinetics are unpredictable (oedema, augmented renal clearance, altered protein binding). Start as soon as haemostasis achieved.

Paediatric dose

Dose: 0.5 mg/kg
Route: Subcutaneous
Frequency: Every 12 hours
Max: 40 mg/dose
Prophylaxis in children ≥2 months: 0.5 mg/kg SC every 12 hours. Infants <2 months: 0.75 mg/kg every 12 hours. Anti-Xa monitoring mandatory.

Dose adjustments

Renal

Reduce to 20 mg once daily if eGFR <30 mL/min (prophylaxis). Anti-Xa monitoring mandatory in renal impairment.

Hepatic

Caution in hepatic impairment — monitor for bleeding.

Paediatric weight-based calculator

Prophylaxis in children ≥2 months: 0.5 mg/kg SC every 12 hours. Infants <2 months: 0.75 mg/kg every 12 hours. Anti-Xa monitoring mandatory.

Clinical pearls

  • Anti-Xa monitoring is essential in major burns — standard prophylactic doses are frequently subtherapeutic due to ARC and altered protein binding. Target anti-Xa 0.2–0.4 units/mL (prophylaxis) 4 hours post-injection.
  • HIT: platelet fall >50% on days 5–14 — stop heparin/LMWH immediately; use fondaparinux or argatroban as alternative. Test for HIT antibodies.
  • Start VTE prophylaxis as soon as haemostasis is secure — burns patients have one of the highest VTE risks of any surgical group

Contraindications

  • Active major bleeding
  • Heparin-induced thrombocytopenia (HIT)
  • Recent neurosurgery or spinal surgery
  • Thrombocytopenia <50 × 10⁹/L

Side effects

  • Bleeding
  • HIT (rare — <1% with LMWH)
  • Injection site bruising/haematoma
  • Hyperkalaemia (aldosterone suppression — prolonged use)
  • Osteoporosis (long-term)

Interactions

  • Antiplatelet agents (additive bleeding risk)
  • NSAIDs (additive bleeding)
  • SSRIs (additive bleeding risk)
  • Warfarin (additive — monitor INR closely during overlap)

Monitoring

  • Anti-Xa level (4h post-injection) in major burns
  • Platelet count every 2–3 days (HIT surveillance days 5–14)
  • Renal function (dose adjustment)
  • Signs of bleeding at surgical sites

Reference: BNFc; BNF 90; BBA VTE Prevention in Burns Guidelines; NICE NG89 (VTE Prophylaxis); BNFc. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Drugs