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BMC Psychiatry

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Open Access 01-12-2023 | Clozapine | Research article

Study on the daily dose and serum concentration of clozapine in psychiatric patients and possible influencing factors of serum concentration

Authors: Taixiu Liu, Peng Gao, Chuange Xie, Heng Zhang, Zheng Shi, Ruirui Chen

Published in: BMC Psychiatry | Issue 1/2023

Abstract

Background

Clozapine is the most effective drug for treatment-resistant schizophrenia, and the dosage and concentration of clozapine in the treatment of mental illness vary greatly in different populations and are affected by many factors.

Methods

The serum clozapine concentration of 3734 psychiatric patients was detected, and data on daily dose, sex, age and other medical records were collected for statistical analysis.

Results

The mean daily dose, mean serum concentration and mean C/D (concentration/dose) ratio of clozapine were 191.02 ± 113.47 mg/day, 326.15 ± 235.66 ng/mL and 1.94 ± 1.25 ng/mL per mg/day, respectively. There was difference in daily dose between sexes, and females had higher daily dose (p <0.01), higher serum clozapine concentrations (p < 0.01) and higher C/D ratios (p < 0.01). There were significant differences in daily dose (p < 0.001), serum drug concentration (p < 0.001) and C/D ratio (p < 0.001) among different age groups. The daily dose decreased with age (p for trend < 0.001), and the C/D ratio increased with age (p for trend < 0.001). Inpatients and outpatients had no difference in daily dose, but inpatients had higher serum concentration (p < 0.001) and C/D ratio (p < 0.001). There was no difference in daily dose among different occupations, but there were significant differences in serum concentration (p < 0.001) and C/D ratio (p < 0.001), and unemployed patients may have higher serum concentration and C/D ratio. Duration of disease, comorbidity, marital status, and psychotic type may influence the daily dose and serum concentration.

Conclusions

The effective daily dose and serum concentration of clozapine in the study area may be lower than recommended levels, and women have higher serum concentrations and slower metabolic rates. With increasing age, the daily dose decreases, and the metabolic rate slows. Inpatient status and occupation of patients may influence the serum concentration and metabolic rate of clozapine.

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Title: Study on the daily dose and serum concentration of clozapine in psychiatric patients and possible influencing factors of serum concentration
Authors: Taixiu Liu
Peng Gao
Chuange Xie
Heng Zhang
Zheng Shi
Ruirui Chen
Publication date: 01-12-2023
Publisher: BioMed Central
Keywords: Clozapine
Schizophrenia
Published in: BMC Psychiatry / Issue 1/2023
Electronic ISSN: 1471-244X
DOI: https://doi.org/10.1186/s12888-023-05078-z

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Study on the daily dose and serum concentration of clozapine in psychiatric patients and possible influencing factors of serum concentration

Abstract

Background

Methods

Results

Conclusions

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Methods

Results

Conclusions

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