Stability and sterility of diluted enoxaparin under three different storage conditions.

Aim: This study assessed whether enoxaparin sodium diluted to a concentration of 20 mg/mL for clinical use with 0.9% sodium chloride remained stable and sterile for up to 43 days under three different storage conditions.

Methods: Enoxaparin dilutions in polypropylene syringes were stored under three different controlled conditions of temperature and light: (i) room temperature (22-26°C) under natural light; (ii) room temperature (22-26°C) in the dark; and (iii) controlled refrigeration (2-8°C) in the dark. A weekly assay of anti-Xa and anti-IIa activity was undertaken to determine if the diluted enoxaparin preparations retained anticoagulant activity, thus remaining suitable for clinical application.

Results: Our findings indicate that diluted enoxaparin, when stored under the tested varied conditions of light and temperature, retained greater than or equal to 90% of baseline anticoagulant activity for anti-Xa and anti-IIa effect for up to 43 days.

Conclusions: The study results are significant for families, in that they suggest that at least a month's supply of enoxaparin could be dispensed at a time, reducing the frequency of patients/families returning for supply and providing a more convenient service for paediatric patients.