Extended Stability of Oxytocin in Ringer's Lactate Solution at 4° and 25°C

Abstract

Purpose Since IV admixtures of oxytocin in the final working concentrations are not commercially available, oxytocin admixtures must be prepared immediately before use or compounded in a sterile laminar flow hood and stored until needed. Although published reports indicate short-term stability of oxytocin in Ringer's lactate solution and Ringer's lactate-dextrose 5%, longer-term stability data at various temperatures are lacking. Methods A stability assay was developed, validated, and executed with oxytocin at two different concentrations in Ringer's lactate solution. Stability was assessed at 4 and 25°C over 31 days. Results This study shows that commonly used dilutions of oxytocin in Ringer's lactate solution retain greater than 90% of initial concentrations, when stored at room temperature or refrigerated for 31 days. These data show that oxytocin admixed with Ringer's lactate solution has extended chemical stability after preparation. Conclusions Demonstration of extended stability of oxytocin in Ringer's lactate solution will allow hospitals to give longer dating to oxytocin IV admixtures, provided they are prepared in a sterile environment and monitored in compliance with USP <797> guidelines. This should help minimize the potentially dangerous practice of admixing this IV solution at the bedside.