Stability of Furosemide 5 mg/mL in Polypropylene Syringes

Furosemide parenteral solutions are routinely used in our hospital. However, the stability in transparent syringes is unknown. In this study, transparent polypropylene syringes were filled with 8 mL and 50 mL of furosemide 5-mg/mL solution. The furosemide was analyzed by high-performance liquid chromatography and assays were performed up to 35 days of storage of the syringes at 4°C protected from light, plus 24 hours at 20°C exposed to daylight. In addition, the appearance and pH of the solutions were determined. A microbiological assay using tryptic soy broth was also performed. Both types of syringes remained colorless, clear, and free from visible particles throughout the study period. The pH did not change, and concentrations remained between 95% and 105% of the stated concentration. None of the syringes filled with culture media exhibited bacterial or fungal growth. In conclusion, ready-to-administer furosemide 5-mg/mL, 8-mL, and 50-mL polypropylene syringes are stable for up to 35 days when stored in a refrigerator at 4°C protected from light, plus 24 hours at 20°C unprotected from light. These results allow maximum storage time in stock and the ability of 24-hour continuous infusion at ambient room temperature without protecting the syringe against light.