Validation and clinical application of a volumetric absorptive microsampling method for 14 psychiatric drugs.

Aim: Volumetric absorptive microsampling offers a hematocrit insensitive way for microsampling. The aim of this study was to develop a method for routine healthcare for 14 antidepressants, antipsychotics and their active metabolites on a single-quadrupole HPLC-MS. A clinical validation study to determine conversion factors from capillary blood to plasma concentration was conducted afterward. Results: The method was validated according to current guidelines except for one substance. Five substances were measured in 49 patient samples and conversion factors could be derived with Passing-Bablok and Bland-Altman analysis. Conclusion: A reliable extraction and analysis method for commonly used antidepressants and antipsychotics was developed and validated. The method with the obtained conversion factors can now be used in routine healthcare.