Study on the pharmacokinetics of clozapine and its metabolites in human blood / 中国法医学杂志

ABSTRACT

Objective To study the pharmacokinetics and detection window of clozapine and its metabolites in human blood, so as to provide experimental basis for forensic cases of identification of clozapine poisoning. Methods 29 Taiyuan Han people's elbow venous blood was collected after given oral administration of 12.5mg clozapine at different time point, in which clozapine and its metabolites were extracted with solid phase extraction (SPE) and determined by HPLC-MS-MS. The qualitative analysis was based on retention time and MRM ions. The quantitative analysis was based on an internal standard method and calibration curve. Using the 3p97 pharmacokinetic software, pharmacokinetic equation of clozapine in the blood were imitated from the C-T data, and pharmacokinetic parameters were calculated. Results The pharmacokinetics of clozapine met a two compartment open model with a first kinetics absorption. The Tmax of clozapine(CLP), demethylclozapine(DMCLP), N-oxidation-clozapine(NO-CLP) respectively were 2.96±1.32h, 8.65±3.00h, 9.31±26.38h; The Cmax of CLP, DMCLP, NO-CLP respectively were 34.68±9.32ng/mL, 11.16±4.15ng/mL, 9.62±13.88ng/mL;The t1/2 of CLP, DMCLP, NO-CLP respectively were 17.02±23.63h, 27.06±12.58h, 41.27±29.75h; The detection window of CLP, DMCLP, NO-CLP respectively were 81.72±26.19h, 93.21±29.40h and 19.93±14.62h. Conclusion The pharmacokinetics of clozapine in blood of Han people is consistent with two compartment open model with a first kinetics absorption. The pharmacokinetics model and parameters of clozapine can provide expirimental basis for forensic identification of clozapine poisoning cases.