Low molecular weight heparin
Enoxaparin sodium
Binds antithrombin and preferentially inhibits factor Xa (with less anti-IIa effect than unfractionated heparin), giving predictable anticoagulation without routine monitoring.
Brands
Clexane · Lovenox
Adult dosing
Maximum No fixed ceiling; dose is weight and indication dependent| Indication | Dose | Route | Frequency |
|---|---|---|---|
| VTE prophylaxis, medical patient | 40 mg | Subcutaneous | Once daily |
| VTE treatment | 1 mg/kgOr 1.5 mg/kg once daily in low-risk outpatients | Subcutaneous | Every 12 hours |
| ACS with planned invasive strategy | 1 mg/kg | Subcutaneous | Every 12 hours |
| Extremes of body weight | Dose on actual body weightConsider anti-Xa monitoring above 120 kg or below 45 kg | Subcutaneous | As above |
Weight-based: Fully weight based — 1 mg/kg per dose for treatment.
Older adults: Reduce prophylactic dose in very low body weight and always dose on measured renal function.
Paediatric dosing
Always confirm the weight and the local paediatric formulary| Indication | Dose | Route | Frequency |
|---|---|---|---|
| Treatment, over 2 months | 1 mg/kg | Subcutaneous | Every 12 hours |
| Treatment, under 2 months | 1.5 mg/kg | Subcutaneous | Every 12 hours |
| Prophylaxis, children | 0.5 mg/kgMax 40 mg per dose | Subcutaneous | Every 12 hours |
Renal adjustment
Move the slider to the patient's eGFRStandard dosing
- eGFR ≥ 30Standard dosing
- eGFR 15-29Treatment 1 mg/kg once daily; prophylaxis 20 mg once daily
- eGFR < 15 or dialysisAvoid — use unfractionated heparin instead
Hepatic adjustment
- Cirrhosis with coagulopathyUse with caution; bleeding risk is not predicted by INR
Practical notes
The things that go wrong at the bedside- Protamine reverses only about 60% of the anti-Xa effect.
- Withhold 12 hours (prophylaxis) or 24 hours (treatment) before neuraxial procedures.
DrZep structured dosing table (demo dataset, formulary-aligned) · DrZep. Confirm every dose against your local formulary and the patient's weight, renal function and comorbidities.
Indications
- Venous thromboembolism treatment and prophylaxis
- ACS anticoagulation alongside antiplatelets
- Bridging anticoagulation
- Thromboprophylaxis in pregnancy and in hospitalised medical patients
Dosing summary
- VTE treatment
- 1 mg/kg subcutaneously every 12 h, or 1.5 mg/kg once daily
- Prophylaxis (medical inpatient)
- 40 mg subcutaneously once daily
- ACS
- 1 mg/kg every 12 h; consider a 30 mg IV bolus with fibrinolysis in patients under 75
- Obesity
- Use actual body weight with anti-Xa monitoring above 150 kg
Organ adjustment
Renal
- eGFR 30-50
- Usually no change; monitor closely
- eGFR 15-29
- Treatment 1 mg/kg once daily; prophylaxis 20 mg once daily
- eGFR < 15 / dialysis
- Use unfractionated heparin instead
Hepatic
- Severe with coagulopathy
- Increased bleeding risk — use with caution and monitor
Monitoring
- 1Platelets at baseline and periodically (HIT surveillance)
- 2Renal function
- 3Haemoglobin and bleeding signs
- 4Anti-Xa levels in pregnancy, extremes of weight or renal impairment
Contraindications & cautions
Do not use / use with care
- Active major bleeding
- Heparin-induced thrombocytopenia (current or historical)
- Severe thrombocytopenia
- Neuraxial anaesthesia within the required interval of a treatment dose
- Acute intracranial haemorrhage
Pregnancy & lactation
- Pregnancy
- Anticoagulant of choice — does not cross the placenta. Dose by weight and plan peripartum interruption.
- Lactation
- Compatible; not absorbed orally by the infant.
Interactions
- Antiplatelets, NSAIDs, thrombolyticsAdditive bleeding riskmajor
- Warfarin / DOACsMajor bleeding unless deliberately overlappedmajor
- ACE inhibitors and potassium-sparing agentsHyperkalaemia through aldosterone suppressionmoderate
Adverse effects
Common
- Injection-site bruising and haematoma
- Mild transaminase rise
- Anaemia
Serious
- Major haemorrhage
- Heparin-induced thrombocytopenia
- Spinal or epidural haematoma with neuraxial procedures
- Hyperkalaemia
- Osteoporosis with prolonged use
Toxicity & overdose
Recognise and treat
- Overdose bleeding: protamine sulfate reverses roughly 60% of anti-Xa activity — give 1 mg per 1 mg enoxaparin given within 8 hours, with a slow infusion to avoid hypotension
Alternatives
- Unfractionated heparin (renal failure, high bleeding risk, need for rapid reversal)
- Fondaparinux
- DOACs for most VTE after the acute phase
Linked diseases & guidelines
Demo monograph for educational use. Always confirm dose, route and interactions against your national formulary and the product label before prescribing.
Demo content. Educational decision support only. Verify every dose, citation and recommendation against your national formulary and the primary source before clinical use.