Low Molecular Weight Heparin — VTE Prophylaxis Pregnancy: In humans there is no evidence that enoxaparin crosses the placental barrier during the second and third trimesters (no information for the first trimester); animal studies have shown no foetotoxicity or teratogenicity. Use during pregnancy only if the physician has established a clear need; monitor pregnant women carefully for bleeding or excessive anticoagulation and warn them of the haemorrhagic risk. If epidural anaesthesia is planned it is recommended to withdraw enoxaparin beforehand. Can be used during breastfeeding (oral absorption of enoxaparin is unlikely).

Enoxaparin (Burns — VTE Prophylaxis)

Brand names: Clexane

Enoxaparin is a low-molecular-weight heparin given subcutaneously for venous thromboembolism prophylaxis in burns patients, who carry a high VTE risk from injury, immobility, and hypercoagulability.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Prophylaxis of venous thromboembolic disease — patients at HIGH risk of thromboembolism: 4,000 IU (40 mg) once daily by subcutaneous injection. Patients at MODERATE risk: 2,000 IU (20 mg) once daily by subcutaneous injection. Prophylaxis of venous thromboembolism in medical patients: 4,000 IU (40 mg) once daily by subcutaneous injection

Route: Subcutaneous injection. Must NOT be administered by the intramuscular route

Frequency: Once daily

Source: UK SPC (eMC) for AROVI 10,000 IU (100mg/1ml) pre-filled syringe with safety device, §4.2 (https://www.medicines.org.uk/emc/product/9329/smpc). The SPC has NO burns-specific prophylaxis regimen — individual thromboembolic risk should be estimated using a validated risk stratification model, and the clinician must confirm the risk category and dose against the local burns/VTE protocol. TIMING: in high-risk patients the 4,000 IU (40 mg) dose is preferably started 12 hours before surgery; if earlier preoperative initiation is needed the last injection should be given no later than 12 hours before surgery and resumed 12 hours after surgery. Preoperative initiation 2 hours before surgery of 2,000 IU (20 mg) was proven effective and safe in moderate-risk surgery. DURATION: in moderate-risk patients maintain treatment for a minimal period of 7-10 days whatever the recovery status, and continue prophylaxis until the patient no longer has significantly reduced mobility; in medical patients treatment is prescribed for at least 6 to 14 days (benefit not established beyond 14 days). Extended thromboprophylaxis up to 5 weeks is recommended after major orthopaedic surgery, and up to 4 weeks after abdominal or pelvic surgery for cancer in patients at high VTE risk. TREATMENT (not prophylaxis) doses for reference: DVT and PE — 150 IU/kg (1.5 mg/kg) SC once daily in uncomplicated patients at low risk of recurrence, or 100 IU/kg (1 mg/kg) SC twice daily in all other patients (obesity, symptomatic PE, cancer, recurrent VTE, proximal thrombosis), for an average of 10 days. Units: the SPC expresses doses in anti-Xa IU with the mg equivalent in brackets (100 IU = 1 mg). §4.3 contraindicates use with spinal/epidural or loco-regional anaesthesia when enoxaparin has been used at TREATMENT doses in the previous 24 hours.

Dose adjustments

Renal

Severe renal impairment (creatinine clearance 15-30 mL/min) — prophylaxis of venous thromboembolic disease: 2,000 IU (20 mg) SC once daily. Treatment doses in the same range: DVT/PE, extended treatment in active cancer, and unstable angina/NSTEMI all reduce to 100 IU/kg (1 mg/kg) SC once daily. Enoxaparin is NOT recommended in end-stage renal disease (creatinine clearance <15 mL/min) outside the haemodialysis extracorporeal-circulation indication. Moderate (30-50 mL/min) and mild (50-80 mL/min) renal impairment — no dose adjustment recommended, but careful clinical monitoring is advised.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to enoxaparin sodium, heparin or its derivatives, including other low molecular weight heparins, or to any of the excipients
History of immune-mediated heparin-induced thrombocytopenia (HIT) within the past 100 days, or the presence of circulating antibodies
Active clinically significant bleeding and conditions with a high risk of haemorrhage — including recent haemorrhagic stroke, gastrointestinal ulcer, malignant neoplasm at high risk of bleeding, recent brain, spinal or ophthalmic surgery, known or suspected oesophageal varices, arteriovenous malformations, vascular aneurysms or major intraspinal/intracerebral vascular abnormalities
Spinal or epidural anaesthesia or loco-regional anaesthesia when enoxaparin sodium has been used for treatment in the previous 24 hours

Side effects

Common: haemorrhage and haemorrhagic anaemia
Common: thrombocytopenia and thrombocytosis
Common: allergic reaction; headache
Rare: immuno-allergic thrombocytopenia with thrombosis, in some cases complicated by organ infarction or limb ischaemia; eosinophilia
Rare: anaphylactic/anaphylactoid reactions including shock; spinal (neuraxial) haematoma. Acute generalized exanthematous pustulosis has been reported in association with enoxaparin treatment

Interactions

Agents which may enhance the risk of haemorrhage should, whenever possible, be discontinued before starting enoxaparin — anticoagulants, platelet inhibitors including acetylsalicylic acid, salicylates, NSAIDs (including ketorolac trometamol), dipyridamole and sulfinpyrazone. If co-administration is essential, conduct close clinical and laboratory monitoring (US label §7)
UK SPC §4.5 was not retrieved in this bundle — verify the full interaction section

Clinical monograph

How it works

It binds antithrombin and accelerates inhibition of factor Xa (and to a lesser extent thrombin), reducing thrombin generation and clot formation.

Prescribing in practice

It is contraindicated in active major bleeding, and dose accumulation occurs in significant renal impairment, increasing bleeding risk.
Burns patients have altered, frequently increased, drug clearance and oedema, so standard fixed prophylactic exposure may be inadequate and anti-Xa-guided dosing is sometimes used.
Heparin-induced thrombocytopenia, though less common than with unfractionated heparin, must be considered if the platelet count falls.

Monitoring

Monitor renal function, platelet count, signs of bleeding, and anti-Xa activity where adequacy of prophylaxis is uncertain.

Counselling the patient

This injection helps prevent blood clots while you are less mobile after your burn.
Report unusual bruising, bleeding, or blood in urine or stool to the team.

Evidence & guidelines

Pharmacological VTE prophylaxis is recommended for at-risk hospitalised patients; burns are recognised as a state of elevated thrombotic risk.

Reference: BBA VTE Prevention in Burns Guidelines; NICE NG89 (VTE Prophylaxis); Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Drugs

Dalteparin (Perioperative VTE Prophylaxis) · Low Molecular Weight Heparin — VTE Prophylaxis