BackgroundHydrocortisone in high doses is given to haemodynamicly unstable patients as a vasopressor. Frequently the same patients have volume restriction, and high concentrations of hydrocortisone are necessary. Although there is no certain evidence of the benefits of continuous infusion over bolus injection, continuous infusion is a well-established practice in our hospital. Manufacturers state that the solution after reconstitution and dilution should be used immediately, however it is not defined how long this infusion can be used after application. There are limited data on the stability of hydrocortisone in concentrations greater than 1 mg/ml.PurposeThe aim of our study was to determine the physical and chemical stability of hydrocortisone sodium succinate in two concentrations (1 mg/ml and 4 mg/ml) at room temperature up to 24 hours after reconstitution and dilution. These are the most frequent circumstances in the wards in our hospital.Material and methodsWe used duplicate samples of hydrocortisone sodium succinate diluted in 0.9% sodium chloride and 5% glucose to concentrations 1 mg/ml and 4 mg/ml. Samples were stored at room temperature (25°C) and at elevated temperature (30°C). Another set of reconstituted and diluted solutions stored at room temperature was protected from light. Concentrations were measured by a validated high-performance liquid chromatography (HPLC) method to determine the percentage of degradation after 3, 5, 7, 9, 12, 24 and 48 hours.ResultsOur study demonstrates that hydrocortisone is equally stable at concentrations 1 mg/ml and 4 mg/ml, in both 0.9% sodium chloride and 5% glucose, regardless whether it is protected from light or not. At room temperature, degradation of hydrocortisone after 12, 24 and 48 hours was 3%, 5% and 10%, respectively. Declines from the initial hydrocortisone concentration in samples stored at 30°C after 3, 5, 12 and 24 hours were 3%, 5%, 9% and 14% respectively.ConclusionHydrocortisone sodium succinate is physically and chemically stable for 12 hours at 25°C.References and/or acknowledgementsSincere thanks to pharmacists in the chair of biopharmaceutics and pharmacokinetics in supporting my idea and completing the survey.No conflict of interest.