Enoxaparin
Brand names: Clexane
Enoxaparin is a low-molecular-weight heparin given by subcutaneous injection for the prevention and treatment of venous thromboembolism and in acute coronary syndromes.
ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.
US labelling (FDA)
Reference — US labelling, may differ from UKSee full prescribing information for dosing and administration information. ( 2 ) 2.1 Pretreatment Evaluation Evaluate all patients for a bleeding disorder before starting enoxaparin sodium treatment, unless treatment is urgently needed. 2.2 Adult Dosage Abdominal Surgery The recommended dose of enoxaparin sodium is 40 mg by subcutaneous injection once a day (with the initial dose given 2 hours prior to surgery) in patients undergoing abdominal surgery who are at risk for thromboembolic complications. The usual duration of administration is 7 to 10 days [see Clinical Studies (14.1) ]. Hip or Knee Replacement Surgery The recommended dose of enoxaparin sodium is 30 mg every 12 hours …
Source: US FDA prescribing information (openFDA / DailyMed), label dated 2024-06-21. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.
Clinical monograph
How it works
It potentiates antithrombin, mainly inhibiting factor Xa (with relatively less effect on thrombin than unfractionated heparin).
Prescribing in practice
- Doses are by indication and body weight; reduce in renal impairment, as it is renally cleared.
- Consider anti-Xa monitoring at extremes of body weight, in significant renal impairment, and in pregnancy.
- Observe timing windows around neuraxial anaesthesia/procedures, and be alert to heparin-induced thrombocytopenia.
Monitoring
Monitor platelets (for heparin-induced thrombocytopenia) and renal function; check anti-Xa levels in selected patients.
Counselling the patient
- It is given as an injection under the skin; rotate injection sites.
- Some bruising at the site is common; report unusual or heavy bleeding.
Evidence & guidelines
LMWH is standard for VTE prophylaxis and treatment and in ACS, per NICE guidance, with renal dose adjustment.
Reference: NICE NG158; RCOG GTG 37a; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).
Related
Curated clinical cross-links plus same-class fallbacks.
- Endotracheal Tube Depth and Tidal Volume Calculator · Airway Management
- IMPROVE VTE Risk Score for Medical Patients · VTE Risk
- BMI + Metabolic Risk Assessment · Obesity
- Ideal & Adjusted Body Weight · Body Composition
- Weight-Based Levothyroxine Dose Calculator · Thyroid
- Body Mass Index (BMI) · Anthropometry
- Major Haemorrhage / Massive Transfusion · BCSH; RCOA; RCEM; RCS — BCSH Guidelines
- Anaemia Investigation · BSH / NICE
- Splenomegaly Workup · BSH; BMJ Best Practice
- Deep Vein Thrombosis Diagnosis and Treatment · NICE CG144 / NICE NG158
- Sickle Cell Crisis · BSH 2021 / BCSH
- Neutropenic Sepsis · NICE CG151 2012 / ESMO
Featured in these MRCEM clinical pathways
Enoxaparin is a core drug in the following exam-focused workups on our sister siteReviseMRCEM.
MRCEM Primary / Intermediate / OSCE candidates: each pathway includes exam-style questions, RCEM/NICE citations, and FAQ summaries.