Physical and chemical stability of palonosetron hydrochloride with glycopyrrolate and neostigmine during simulated y-site administration.

The objective of this study was to evaluate the physical and chemical stability of undiluted palonosetron hydrochloride 50 mcg/mL when mixed with undiluted glycopyrrolate 0.2 mg/mL and neostigmine methylsulfate 0.5 mg/mL during simulated Y-site administration. Duplicate test samples were prepared by admixing 7.5 mL of palonosetron hydrochloride with 7.5 mL of glycopyrrolate and neostigmine methylsulfate injections. Physical stability was assessed by using a multi-step evaluation procedure that included both turbidimetric and particulate measurements and visual inspection. Chemical stability was assessed by using a multi-step evalutation procedure that included both turbidimetric and particulate measurements and visual inspection. Chemical stability was assessed by using stability-indicating high-performance liquid chromatography analytical techniques based on the determination of drug concentrations. Evaluations were perfromed initially upon mixing and 1 and 4 hours after mixing. The samples were clear and colorless when viewed with a Tyndall beam. Measured turbidity remained unchanged and particulate content was low and exhibited little change. High-performance liquid chromatography analysis found palonosetron hydrochloride and both glycopyrrolate and neostigmine methylsulfate remained stable throughout the 4-hour test with no drug loss. Palonosetron hydrochloride is physically compatible and chemically stable with glycopyrrolate and neostigmine methylsulfate during simulated Y-site administration.