title: Stability of ertapenem 100 mg/mL in polypropylene syringes stored at 25, 4, and -20 °C.
abstract: OBJECTIVE
  The stability of ertapenem solution in syringes at room, refrigerator, and freezer temperatures was determined to establish options for extended storage.
  
  
  METHODS
  Six replicate solutions of ertapenem (100 mg/mL) in 0.9% sodium chloride injection were prepared in 20-mL polypropylene syringes and stored at 25, 4, or -20 °C. Syringe samples were collected immediately after preparation and at preselected time points and assayed by a validated high-performance liquid chromatography (HPLC) method. The ertapenem solution was considered stable if at least 90% of the mean initial concentration remained at the time of HPLC analysis.
  
  
  RESULTS
  The mean±S.D. baseline ertapenem concentration across all stability studies was 109.9±9.2 mg/mL. One hour after preparation, the mean±S.D. ertapenem concentration of samples kept at room temperature was 87.8±4.6% of the initial concentration. After 24 and 48 hours of refrigeration, mean±S.D. drug concentrations had declined to 93.6±5.9% and 86.2±4.3% of the respective baseline concentrations. Frozen syringes required 1 hour to thaw at room temperature; after 14 and 28 days of frozen storage, the mean±S.D. ertapenem concentrations of these samples 4 hours after thawing were 93.4±3.5% and 86.4±2.6% of the respective baseline values.
  
  
  CONCLUSIONS
  Ertapenem 100 mg/mL prepared in 20-mL polypropylene syringes was stable at room temperature for approximately 30 minutes. Room-temperature stability was extended to 4 hours after 24 hours of refrigeration. After being frozen for 14 or 28 days, ertapenem was stable for 3-5 hours after removal from the freezer.
authors.affiliation: Jami G. Jain, Pharm.D., BCPS, is Infectious Diseases Pharmacotherapy Fellow; Christina Sutherland, B.S., is Research Technologist; David P. Nicolau, Pharm.D., FCCP, FIDSA, is Director; and Joseph L. Kuti, Pharm.D., is Associate Director, Clinical and Economic Studies, Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT.
authors.forename: Jami G
authors.initials: JG
authors.lastname: Jain
authors.affiliation: Jami G. Jain, Pharm.D., BCPS, is Infectious Diseases Pharmacotherapy Fellow; Christina Sutherland, B.S., is Research Technologist; David P. Nicolau, Pharm.D., FCCP, FIDSA, is Director; and Joseph L. Kuti, Pharm.D., is Associate Director, Clinical and Economic Studies, Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT.
authors.forename: Christina
authors.initials: C
authors.lastname: Sutherland
authors.affiliation: Jami G. Jain, Pharm.D., BCPS, is Infectious Diseases Pharmacotherapy Fellow; Christina Sutherland, B.S., is Research Technologist; David P. Nicolau, Pharm.D., FCCP, FIDSA, is Director; and Joseph L. Kuti, Pharm.D., is Associate Director, Clinical and Economic Studies, Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT.
authors.forename: David P
authors.initials: DP
authors.lastname: Nicolau
authors.affiliation: Jami G. Jain, Pharm.D., BCPS, is Infectious Diseases Pharmacotherapy Fellow; Christina Sutherland, B.S., is Research Technologist; David P. Nicolau, Pharm.D., FCCP, FIDSA, is Director; and Joseph L. Kuti, Pharm.D., is Associate Director, Clinical and Economic Studies, Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT. joseph.kuti@hhchealth.org.
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Kuti
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D004356:Drug Storage; D000077727:Ertapenem; D019999:Pharmaceutical Solutions / Q000737:chemistry; D011126:Polypropylenes / Q000737:chemistry*; D013594:Syringes; D013696:Temperature; D013997:Time Factors; D047090:beta-Lactams / Q000737:chemistry*
chemical_list: D019999:Pharmaceutical Solutions; D011126:Polypropylenes; D047090:beta-Lactams; D000077727:Ertapenem