title: Stability of extemporaneously compounded dexamethasone in glass and plastic bottles and plastic syringes.
abstract: BACKGROUND
  Dexamethasone is widely used to treat rheumatic and endocrine disorders and chemotherapy-induced nausea and vomiting. A palatable, alcohol-free liquid formulation, with a suitable concentration to allow reasonable administration volume, is available only via extemporaneous compounding.
  
  
  OBJECTIVE
  To evaluate the stability of dexamethasone suspensions in commercially available vehicles (Oral Mix and Oral Mix SF) in various types of containers after storage at 25°C and 4°C for up to 91 days.
  
  
  METHODS
  Dexamethasone suspensions (1 mg/mL) were prepared in Oral Mix and Oral Mix SF and then transferred to amber glass and plastic prescription bottles and plastic oral syringes. Suspensions in all 3 types of containers were stored at 25°C; suspensions in glass and plastic bottles were also stored at 4°C. Samples were collected weekly from each container up to 28 days and then every 2 weeks up to 91 days. The samples were analyzed by a validated, stability-indicating high-performance liquid chromatography - ultraviolet detection method. A suspension was considered stable if it maintained at least 90% of its initial dexamethasone concentration. Changes in colour, taste, odour, precipitation (and ease of resuspension), and pH were used to assess physical compatibility.
  
  
  RESULTS
  All suspensions maintained at least 96% of the original concentration for up to 91 days with storage at 25°C or at 4°C. No notable changes in colour, taste, odour, precipitation, or pH were observed over the 91-day period.
  
  
  CONCLUSIONS
  Dexamethasone suspensions (1 mg/mL) in Oral Mix and Oral Mix SF, stored in amber glass or plastic bottles or plastic syringes at 25°C or in amber glass or plastic bottles at 4°C can be expected to remain stable for up to 91 days.
authors.affiliation: BS(Pharm), PharmD, FASHP, FCCP, FCSHP, is Professor, Faculty of Pharmaceutical Sciences, and Distinguished University Scholar, The University of British Columbia; and Clinical Pharmacy Specialist, Department of Pharmacy, Children's and Women's Health Centre of British Columbia, Vancouver, British Columbia. She is also the Editor of the CJHP .
authors.forename: Mary H H
authors.initials: MH
authors.lastname: Ensom
authors.affiliation: BSc, is a Research Consultant, Department of Pharmacy, Children's and Women's Health Centre of Columbia, Vancouver, British Columbia.
authors.forename: Diane
authors.initials: D
authors.lastname: Décarie
keywords: dexamethasone; high-performance liquid chromatography; stability; suspension