enoxaparin sodium: clinical use

Prescribing considerations

• Confirm indication, current weight, renal function, bleeding risk, haemostasis-altering medicines and planned invasive or neuraxial procedures.
• Low molecular weight heparins are not interchangeable unit for unit; prescribe and document the intended product clearly.
• Exposure and bleeding risk increase with renal impairment, older age and low body weight; hepatic impairment also requires caution.
• Record the trade name and batch number for biological-medicine traceability.
• Coordinate interruption and restarting around spinal or epidural procedures using product-specific guidance and individual risk assessment.

Contraindications and cautions

• Hypersensitivity to enoxaparin, heparin, other low molecular weight heparins or an excipient
• Immune-mediated heparin-induced thrombocytopenia within the previous 100 days or circulating HIT antibodies
• Active clinically significant bleeding or a condition carrying a high haemorrhage risk
• Spinal, epidural or locoregional anaesthesia where recent treatment-level enoxaparin exposure makes it contraindicated

Monitoring

• Assess for bleeding, anaemia, thrombosis and injection-site reactions.
• Check platelets before treatment and when clinically indicated; investigate a significant fall or symptoms suggesting HIT immediately.
• Review renal function, particularly in older adults, acute illness or changing kidney function.
• Monitor potassium in patients with diabetes, renal failure, metabolic acidosis or potassium-raising medicines.
• Routine aPTT is unsuitable for measuring activity; anti-Xa measurement may be considered in selected higher-risk situations.

Clinical pharmacology

A porcine-derived low molecular weight heparin acting through antithrombin, with substantially greater anti-factor Xa than anti-factor IIa activity. Subcutaneous bioavailability based on anti-Xa activity is close to complete; active exposure rises as renal function declines.

Formulation and product differences

• Selected products are clear to yellowish, single-use solutions in pre-filled syringes containing water for injections.
• Clexane syringes may have an automatic safety system; some presentations are graduated while others are not.
• The selected Inhixa syringe is not graduated and may have one of several needle-guard designs.
• Products should not be substituted unit for unit without checking the proprietary product instructions.