To conduct an analysis of the concentration monitoring results for 10 antipsychotic drugs in a tertiary general hospital, and compare them based on clinical and domesticand/international standards, with an aim to provide a solid clinical foundation for the rational and safe utilization of antipsychotic medications.

The domestic and international standards related to therapeutic drug monitoring (TDM) of 10 antipsychotic drugs were compared. The results of antipsychotic drug concentration monitoring of schizophrenia patients who clinically achieved therapeutically effective treatment at Linyi Central Hospital from January 2019 to December 2022 were then analyzed based on the two standards mentioned above. The differences in the results of drug concentrations in patients of different genders and ages were compared.

Based on the results of antipsychotic drug concentration monitoring in 7145 cases, according to the TDM guidelines of the Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie (AGNP) and the 2022 Chinese Psychiatric Expert Consensus on Clinical Application of TDM (hereinafter referred to as "Expert Consensus"), the overall difference in the incidence of drug concentrations below the reference concentration, reasonable concentrations, and laboratory alert values was not statistically significant. According to the Expert Consensus, the incidence of amisulpride concentrations higher than the reference concentration and critical values in the sample was significantly lower compared with that based on the AGNP guidelines (P<0.01), whereas the incidence of olanzapine critical values was significantly higher than that based on the AGNP guidelines (P<0.05). According to the Expert Consensus, the incidence of olanzapine critical values in the sample was significantly higher than that based on the AGNP guidelines (P<0.05). According to the Expert Consensus, the difference in Treatment Emergent Symptom Scale (TESS) scores of patients with olanzapine and amisulpride concentrations lower/higher than the alert value in the sample was statistically significant (P<0.05), while the difference in TESS scores of patients with amisulpride concentrations lower/higher than the alert value was not statistically significant according to the AGNP criteria. Under the premise that there was no statistically significant difference in the mean dosage of medication, the drug concentrations of amisulpride, sulpiride, clozapine, olanzapine, and chlorpromazine were significantly higher in female patients than in male patients (P<0.01), and the drug concentration of aripiprazole was significantly higher in males than in females (P<0.01). The differences in the median drug concentrations of paliperidone, clozapine, quetiapine, olanzapine, and risperidone among different age subgroups were all statistically significant (P<0.05). In the paliperidone group, there was a statistically significant difference between the adult and elderly groups (P<0.05); in the clozapine group, there was a statistically significant difference between the adolescent and elderly groups, and between the adult and elderly groups (P<0.01); in the quetiapine group, there was a statistically significant difference between the elderly and adolescent groups, between the elderly and adolescent groups, and between the adult and adolescent groups (P<0.01); in the olanzapine group, there was a statistically significant difference between the elderly and adolescent group, and between the elderly and adult groups (P<0.01); in the risperidone group, there was a statistically significant difference between the adult and elderly groups (P<0.01) and between the adolescent and elderly groups (P<0.05); there was no significant difference in the other drug concentrations among different age groups.

The Expert Consensus can provide more valuable guidance for medication usage in domestic general hospitals. It is also recommended that individualized medication regimens be developed based on TDM results, taking into account the specific type of medication, gender, and age of each patient. Regular evaluation of their clinical appropriateness should be conducted to not only reduce medical malpractice and ensure patient safety but also enhance hospital management.