title: Stability of furosemide and chlorothiazide stored in syringes.
abstract: OBJECTIVE
  The results of a study to determine the stability of solutions of furosemide and chlorothiazide over 96 hours are reported.
  
  
  METHODS
  Chlorothiazide and furosemide were diluted in 5% dextrose USP to final concentrations of 10 and 1 mg/mL, respectively, and combined. In addition, sample solutions of chlorothiazide in dextrose, furosemide in dextrose, and dextrose alone were prepared for control purposes. The resulting solutions were analyzed immediately after preparation and 24, 48, 72, and 96 hours later using a liquid chromatography-tandem mass spectroscopy (LC-MS/MS) system with an electrospray ionization source. Mixtures and samples were diluted 10,000-fold prior to LC-MS/MS analysis so that concentrations of both drugs would be within the assay's linear range of detection.
  
  
  RESULTS
  LC-MS/MS analysis showed that chlorothiazide typically eluted at 2.6 minutes and furosemide at 4.8 minutes. Each compound was degraded by exposure to strong ultraviolet light in a time-dependent manner. Both unmixed and mixed solutions retained over 90% of the original concentrations of chlorothiazide and furosemide for up to 96 hours. Furosemide and chlorothiazide are commonly used concomitantly to maximize diuresis in pediatric patients; the study findings suggest that solutions of furosemide and chlorothiazide can be combined in the same syringe without loss of stability for up to 96 hours.
  
  
  CONCLUSIONS
  Solutions of chlorothiazide (10 mg/mL) and furosemide (1 mg/mL) stored either separately or together in polypropylene syringes remained stable for up to 96 hours at room temperature and protected from light.
authors.affiliation: Jeffrey J. Cies, Pharm.D., M.P.H., BCPS (AQ-ID), is Pharmacist, St. Christopher's Hospital for Children, Philadelphia, PA, and Pharmacy Clinical Coordinator, Critical Care, and Infectious Diseases Clinical Pharmacist, Alfred I. duPont Hospital for Children, Wilmington, DE. Wayne S. Moore II, Pharm.D., is Pharmacist, Alfred I. duPont Hospital for Children. Arun Chopra, M.D., is Clinician, NYU Langone Medical Center, and Chief, Section of Critical Care Medicine, NYU School of Medicine, New York, NY. Guizhen Lu, B.S., is Research Assistant; and Robert W. Mason, Ph.D., is Head of Clinical Biochemistry, Nemours Biomedical Research, Alfred I. duPont Hospital for Children. jeffrey.cies@gmail.com.
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Cies
authors.affiliation: Jeffrey J. Cies, Pharm.D., M.P.H., BCPS (AQ-ID), is Pharmacist, St. Christopher's Hospital for Children, Philadelphia, PA, and Pharmacy Clinical Coordinator, Critical Care, and Infectious Diseases Clinical Pharmacist, Alfred I. duPont Hospital for Children, Wilmington, DE. Wayne S. Moore II, Pharm.D., is Pharmacist, Alfred I. duPont Hospital for Children. Arun Chopra, M.D., is Clinician, NYU Langone Medical Center, and Chief, Section of Critical Care Medicine, NYU School of Medicine, New York, NY. Guizhen Lu, B.S., is Research Assistant; and Robert W. Mason, Ph.D., is Head of Clinical Biochemistry, Nemours Biomedical Research, Alfred I. duPont Hospital for Children.
authors.forename: Wayne S
authors.initials: WS
authors.lastname: Moore
authors.affiliation: Jeffrey J. Cies, Pharm.D., M.P.H., BCPS (AQ-ID), is Pharmacist, St. Christopher's Hospital for Children, Philadelphia, PA, and Pharmacy Clinical Coordinator, Critical Care, and Infectious Diseases Clinical Pharmacist, Alfred I. duPont Hospital for Children, Wilmington, DE. Wayne S. Moore II, Pharm.D., is Pharmacist, Alfred I. duPont Hospital for Children. Arun Chopra, M.D., is Clinician, NYU Langone Medical Center, and Chief, Section of Critical Care Medicine, NYU School of Medicine, New York, NY. Guizhen Lu, B.S., is Research Assistant; and Robert W. Mason, Ph.D., is Head of Clinical Biochemistry, Nemours Biomedical Research, Alfred I. duPont Hospital for Children.
authors.forename: Arun
authors.initials: A
authors.lastname: Chopra
authors.affiliation: Jeffrey J. Cies, Pharm.D., M.P.H., BCPS (AQ-ID), is Pharmacist, St. Christopher's Hospital for Children, Philadelphia, PA, and Pharmacy Clinical Coordinator, Critical Care, and Infectious Diseases Clinical Pharmacist, Alfred I. duPont Hospital for Children, Wilmington, DE. Wayne S. Moore II, Pharm.D., is Pharmacist, Alfred I. duPont Hospital for Children. Arun Chopra, M.D., is Clinician, NYU Langone Medical Center, and Chief, Section of Critical Care Medicine, NYU School of Medicine, New York, NY. Guizhen Lu, B.S., is Research Assistant; and Robert W. Mason, Ph.D., is Head of Clinical Biochemistry, Nemours Biomedical Research, Alfred I. duPont Hospital for Children.
authors.forename: Guizhen
authors.initials: G
authors.lastname: Lu
authors.affiliation: Jeffrey J. Cies, Pharm.D., M.P.H., BCPS (AQ-ID), is Pharmacist, St. Christopher's Hospital for Children, Philadelphia, PA, and Pharmacy Clinical Coordinator, Critical Care, and Infectious Diseases Clinical Pharmacist, Alfred I. duPont Hospital for Children, Wilmington, DE. Wayne S. Moore II, Pharm.D., is Pharmacist, Alfred I. duPont Hospital for Children. Arun Chopra, M.D., is Clinician, NYU Langone Medical Center, and Chief, Section of Critical Care Medicine, NYU School of Medicine, New York, NY. Guizhen Lu, B.S., is Research Assistant; and Robert W. Mason, Ph.D., is Head of Clinical Biochemistry, Nemours Biomedical Research, Alfred I. duPont Hospital for Children.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Mason
mesh_terms: D002740:Chlorothiazide / Q000032:analysis* / Q000592:standards; D002853:Chromatography, Liquid / Q000379:methods; D004232:Diuretics / Q000032:analysis* / Q000592:standards; D004355:Drug Stability; D004356:Drug Storage / Q000379:methods / Q000592:standards; D005665:Furosemide / Q000032:analysis* / Q000592:standards; D006801:Humans; D019999:Pharmaceutical Solutions / Q000592:standards; D013594:Syringes / Q000592:standards; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D004232:Diuretics; D019999:Pharmaceutical Solutions; D002740:Chlorothiazide; D005665:Furosemide