Therapeutic Drug Monitoring of Quetiapine in Child and Adolescents

Therapeutic drug monitoring (TDM) is based on the assumption that there is a definable relationship between plasma concentration and clinical effects (therapeutic effect, adverse effects and toxicity). According to the AGNP-TDM expert group consensus guidelines (Baumann et al., 2004) for some age groups of patients including children, adolescents and elderly patients it is precisely the lack of psychopharmacological data, which strongly suggests the use of TDM in order to avoid problems (e.g. non-response, side-effects) during medications.

The aim of this ongoing study was to determine trough steady-state serum concentrations of quetiapine in children and adolescents. Quetiapine, is a newly developed atypical neuroleptic drug that is effective in treating productive symptoms of psychosis while it appears not to provoke more extra-pyramidal side effects than placebo treatment. We used high-performance liquid chromatography (HPLC) with column switching which allows direct injection of plasma into the HPLC system in combination with a UV detector for the assessment of quetiapiene concentrations.

Our preliminary results demonstrated that the quetiapine plasma concentrations determined in our study population of adolescents are higher than the recommended plasma concentration ranges for TDM in adults (70–170 ng/ml).

References: Baumann P, Hiemke C, Ulrich S, Eckermann G, Gaertner I, Gerlach M, Kuss H-J, Laux G, Müller-Oerlinghausen B, Rao ML, Riederer P, Zernig G (2004) The AGNP-TDM expert group consensus guidelines: Therapeutic drug monitoring in Psychiatry, Pharmacopsychiatry 37 (2004) H. 243–265.