Stability study of dezocine in 0.9% sodium chloride solutions for patient-controlled analgesia administration

BACKGROUND: Dezocine, a mixed agonist/antagonist of opioid receptors, has been used in iv patient-controlled analgesia (PCA) pumps for postoperative pain control. The aim of this study was to investigate the physicochemical stability of dezocine solutions in 0.9% sodium chloride for injection for PCA administration. METHODS: Solutions of dezocine (0.3, 0.45, or 0.6 mg/mL in 0.9% sodium chloride for injection) were stored in polyolefin bags and glass bottles. Their stabilities at storage conditions of 4°C for 14 days and 25°C for 72 hours were studied. For all preparations, physical characteristics (including pH, color, and presence of precipitates) were evaluated. Each preparation of dezocine was also analyzed using a stability-indicating high-performance liquid chromatography method. A solution was considered stable if it maintained at least 90% of its initial concentration. RESULTS: No notable changes in pH, color, or precipitation were observed in any of the prepared solutions over the testing period. All formulations maintained >97% of the initial dezocine concentration under the storage conditions evaluated. CONCLUSIONS: Dezocine solutions at 0.3, 0.45, or 0.6 mg/mL in 0.9% sodium chloride for PCA administration were stable for 72 hours at 25°C and for 14 days at 4°C when packaged in polyolefin bags or glass bottles and protected from light.