Therapeutic Drug Monitoring of Psychotropic Drugs in China: A Nationwide Survey

Objective: To understand the status of therapeutic drug monitoring (TDM) of psychotropic drugs in psychiatric facilities in mainland China and to lay the foundation for improvement of TDM in psychiatry. Methods: A cross-sectional survey was conducted with a locally developed questionnaire among psychiatric facilities in which TDM of psychotropic drugs was available. The questionnaire included laboratory situations, implementation of TDM, equipment and analytical methods, internal quality control (IQC), and external quality assessment (EQA). Results: Forty-seven of the 58 delivered questionnaires were collected from the psychiatric facilities involving 26 provinces in mainland China. The response rate was 81.0%. Among all facilities surveyed, lithium was the most common psychotropic drug (68.1% of the laboratories) monitored by TDM, followed by clozapine (44.7%), carbamazepine (25.5%), chlorpromazine (21.3%), norclozapine (19.1%), risperidone (19.1%), paliperidone (17.0%), valproic acid (14.9%), and quetiapine (10.6%). Only 10.2% of the laboratories had recommendations for dose adjustments based on their TDM reports. Others only provided drug concentration results with no clinical recommendations. The analytical methods used included high-performance liquid chromatography, liquid chromatography with tandem mass spectrometric detection, and immunoassay. For lithium, most hospitals used ion-selective electrode methods. IQC and EQA were still in their infancy. Conclusions: This first nationwide survey showed that TDM has been available in a considerable number of psychiatric hospitals across China. Though current equipment and analytical methods meet the TDM need, much improvement is needed, particularly in new analytical method development, interpretation of results, consultation services, and quality control, including IQC and EQA. Guidance or consensus guideline for TDM of psychotropic drugs in the Chinese language is also urgently required.