Pharmacopsychiatry
DOI: 10.1055/s-0043-109695
Original Paper
© Georg Thieme Verlag KG Stuttgart · New York

Relationship Between Daily Dose, Serum Concentration, and Clinical Response to Quetiapine in Children and Adolescents with Psychotic and Mood Disorders

Laura Albantakis1, *, Karin Egberts1, Rainer Burger2, Christine Kulpok1, Claudia Mehler-Wex1, 3, 4, Regina Taurines1, Stefan Unterecker2, Christoph Wewetzer5, Marcel Romanos1, Manfred Gerlach1
  • 1Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital of Würzburg, Centre for Mental Health,Würzburg, Germany,
  • 2Department of Psychiatry, Psychosomatics and Psychotherapy,University Hospital of Würzburg, Centre for Mental Health, Würzburg, Germany
  • 3HEMERA Private Hospital for Mental Health, Adolescents and Young Adults, Bad Kissingen, Germany
  • 4Affiliation between January 2007 and December 2008: University Hospital of Ulm, Department of Child and Adolescent Psychiatry and Psychotherapy, Ulm, Germany
  • 5Clinics of the City Cologne GmbH, Clinic for Child and Adolescent Psychiatry and Psychotherapy, Cologne, Germany
Further Information

Publication History

received 03 August 2016
revised 17 April 2017

accepted 19 April 2017

Publication Date:
23 May 2017 (eFirst)

Abstract

Introduction In child and adolescent psychiatry, therapeutic drug monitoring (TDM) is strongly recommended. However, therapeutic ranges (TR) are defined only for adults. The objectives of this naturalistic study were to assess the relationships between serum quetiapine concentration, daily dose, and clinical outcomes as well as the determinants of pharmacokinetic variability. Furthermore, it was elucidated whether the recommended TR for adult patients with psychotic disorders is valid for children and adolescents.

Methods TDM was performed in 180 pediatric patients treated with quetiapine. Psychopathological changes were assessed by the Clinical Global Impression – Improvement scale (CGI-I). Adverse drug reactions (ADRs) were assessed by using a short form of the Udvalg for Kliniske Undersogelser (UKU) side effect rating scale.

Results A weak positive linear relationship between daily dose (mean 349.9±248.9 mg/day) and serum concentration of quetiapine (rs=0.496, p<0.001) was found (mean age 15.6±1.9 years, 45.6% male, 31.1% monotherapy), but no relationship between serum concentration and clinical outcome was found. Dose variation accounted for only 12.5% (rs 2=0.125) of the variability of serum concentrations. No effects by gender, age, body weight, smoking habits, and co-medication were found. The majority of patients with psychotic (67.8%) and mood disorders (74.5%) showed a serum concentration below the suggested lower limit (100 ng/mL) of the TR for adults.

Discussion There are several limitations of this study because of the naturalistic design, and our results should therefore be interpreted with caution. Notwithstanding, our data suggest that the lower limit of the TR for quetiapine is lower than the limit in adult patients.

* Current address: Max Planck Institute of Psychiatry, Kraepelinstraße 2-10, 80804 München