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Open access

Uta Neumann, Daniela Burau, Sarah Spielmann, Martin J Whitaker, Richard J Ross, Charlotte Kloft, and Oliver Blankenstein


Due to the lack of paediatric-licensed formulations, children are often treated with individualized pharmacy-compounded adult medication. An international web-based survey about the types of medication in children with adrenal insufficiency (AI) revealed that the majority of paediatric physicians are using pharmacy-compounded medication to treat children with AI. Observations of loss of therapy control in children with congenital adrenal hyperplasia with compounded hydrocortisone capsules and regained control after prescribing a new hydrocortisone batch led to this ‘real world’ evaluation of pharmacy-compounded paediatric hydrocortisone capsules.


Capsule samples were collected randomly from volunteering parents of treated children suffering from congenital adrenal hyperplasia from all over Germany. Analysis of net mass and hydrocortisone content by high-performance liquid chromatography with ultraviolet (HPLC-UV) detection method was performed based on the European Pharmacopeia.


In a total of 61 batches that were sent, 5 batches could not be analysed because of missing dose information, insufficient number of capsules or were not possible to be evaluated. Fifty-six batches containing 1125 capsules were evaluated. 21.4% of the batches revealed insufficiency in uniformity of net mass or drug content and additional 3.6% failed because they did not contain the labelled drug.


Compounded medication is a possible cause of variation of steroid doses in children with adrenal insufficiency or congenital adrenal hyperplasia, putting these vulnerable patients at risk of poor disease control and adrenal crisis. These data may apply to other individualized compounded oral medication as well, emphasizing the need for development of licensed paediatric formulations approved by regulatory authorities.

Free access

Viktoria Stachanow, Uta Neumann, Oliver Blankenstein, Uwe Fuhr, Wilhelm Huisinga, Robin Michelet, Nicole Reisch, and Charlotte Kloft


Prenatal dexamethasone therapy is used in female foetuses with congenital adrenal hyperplasia to suppress androgen excess and prevent virilisation of the external genitalia. The traditional dexamethasone dose of 20 µg/kg/day has been used since decades without examination in clinical trials and is thus still considered experimental.


As the traditional dexamethasone dose potentially causes adverse effects in treated mothers and foetuses, we aimed to provide a rationale of a reduced dexamethasone dose in prenatal congenital adrenal hyperplasia therapy based on a pharmacokinetics-based modelling and simulation framework.


Based on a published dexamethasone dataset, a nonlinear mixed-effects model was developed describing maternal dexamethasone pharmacokinetics. In stochastic simulations (n = 1000), a typical pregnant population (n = 124) was split into two dosing arms receiving either the traditional 20 µg/kg/day dexamethasone dose or reduced doses between 5 and 10 µg/kg/day. Target maternal dexamethasone concentrations, identified from the literature, served as a threshold to be exceeded by 90% of mothers at a steady state to ensure foetal hypothalamic-pituitary-adrenal axis suppression.


A two-compartment dexamethasone pharmacokinetic model was developed and subsequently evaluated to be fit for purpose. The simulations, including a sensitivity analysis regarding the assumed foetal:maternal dexamethasone concentration ratio, resulted in 7.5 µg/kg/day to be the minimum effective dose and thus our suggested dose.


We conclude that the traditional dexamethasone dose is three-fold higher than needed, possibly causing harm in treated foetuses and mothers. The clinical relevance and appropriateness of our recommended dose should be tested in a prospective clinical trial.

Free access

Robin Michelet, Johanna Melin, Zinnia P Parra‐Guillen, Uta Neumann, Martin J Whitaker, Viktoria Stachanow, Wilhelm Huisinga, John Porter, Oliver Blankenstein, Richard J Ross, and Charlotte Kloft

Free access

Robin Michelet, Johanna Melin, Zinnia P. Parra-Guillen, Uta Neumann, J Martin Whitaker, Viktoria Stachanow, Wilhelm Huisinga, John Porter, Oliver Blankenstein, Richard J. Ross, and Charlotte Kloft


Accurate hydrocortisone dosing in children with adrenal insufficiency is important to avoid the risks of over and under treatment including iatrogenic Cushing’s syndrome and adrenal crisis.


To establish a population pharmacokinetic model of hydrocortisone in children and use this to refine hydrocortisone replacement regimens.

Design and methods:

Pharmacokinetic study of hydrocortisone granules, available in 0.5, 1, 2 and 5 mg dose strengths, in 24 children with adrenal insufficiency aged 2 weeks to 6 years. Cortisol concentrations quantified by LC-MS/MS were used to refine an adult pharmacokinetic model to a paediatric population model which was then used to simulate seven different hydrocortisone treatment regimens.


Pre-dose cortisol levels were undetectable in 54% of the 24 children. The developed pharmacokinetic model had good predictive performance. Simulations for the seven treatment regimens using either three- or four-times daily dosing showed treatment regimens delivered an AUC0- 24h within the 90% reference range for healthy children except in neonates where two regimens had an AUC below the 5th percentile. Cortisol concentrations at individual time points in the 24 h were outside the 90% reference range for healthy individuals in 50%, 55–65% and 70–75% for children, infants and neonates, respectively, with low cortisol levels being most prevalent.


Current paediatric hydrocortisone treatment regimens based on either three- or four-times daily administration replicate cortisol exposure based on AUC0- 24h, but the majority of cortisol levels are above or below physiological cortisol levels with low levels very common before the next dose.