Chemical stability of meperidine hydrochloride in polypropylene syringes.

The physical and chemical stability of preservative-free meperidine hydrochloride solutions in polypropylene syringes was studied. Solutions of meperidine hydrochloride were diluted in dextrose 5% and normal saline to 0.25, 1, 10, 20, and 30mg/mL, repectively, and stored at either 22 deg C or 4 deg C for 28 days. All solutions were protected from light druing storage. Triplicate samples were taken from each syringe on days zero, one, three, seven, 14 and 28 and frozen at -72 deg C. Samples were analyzed in duplicate using a stability-indiicating high-pressure liquid chromatography assay. All samples remained colorless and free of precipitate throughout the course of the study. The concentration of meperidine remaining after the 28-day storage period was greater than 90% of the initial concentration for all the concentrations, diluents and temperatures studied.