Forskning
Udskriv Udskriv
Switch language
Region Hovedstaden - en del af Københavns Universitetshospital
Udgivet

The significance of sampling time in therapeutic drug monitoring of clozapine

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Harvard

APA

CBE

MLA

Vancouver

Author

Jakobsen, M I ; Larsen, J R ; Svensson, C K ; Johansen, S S ; Linnet, K ; Nielsen, J ; Fink-Jensen, A. / The significance of sampling time in therapeutic drug monitoring of clozapine. I: Acta Psychiatrica Scandinavica. 2017 ; Bind 135, Nr. 2. s. 159-169.

Bibtex

@article{0404ab52c53a445a874957065ee1cef5,
title = "The significance of sampling time in therapeutic drug monitoring of clozapine",
abstract = "OBJECTIVE: Therapeutic drug monitoring (TDM) of clozapine is standardized to 12-h postdose samplings. In clinical settings, sampling time often deviates from this time point, although the importance of the deviation is unknown. To this end, serum concentrations (s-) of clozapine and its metabolite N-desmethyl-clozapine (norclozapine) were measured at 12 ± 1 and 2 h postdose.METHOD: Forty-six patients with a diagnosis of schizophrenia, and on stable clozapine treatment, were enrolled for hourly, venous blood sampling at 10-14 h postdose.RESULTS: Minor changes in median percentage values were observed for both s-clozapine (-8.4{\%}) and s-norclozapine (+1.2{\%}) across the 4-h time span. Maximum individual differences were 42.8{\%} for s-clozapine and 38.4{\%} for s-norclozapine. Compared to 12-h values, maximum median differences were 8.4{\%} for s-clozapine and 7.3{\%} for s-norclozapine at deviations of ±2 h. Maximum individual differences were 52.6{\%} for s-clozapine and 105.0{\%} for s-norclozapine. The magnitude of s-clozapine differences was significantly associated with age, body mass index and the presence of chronic basophilia or monocytosis.CONCLUSION: The impact of deviations in clozapine TDM sampling time, within the time span of 10-14 h postdose, seems of minor importance when looking at median percentage differences. However, substantial individual differences were observed, which implies a need to adhere to a fixed sampling time.",
keywords = "Adult, Antipsychotic Agents, Clozapine, Dose-Response Relationship, Drug, Drug Administration Schedule, Drug Monitoring, Female, Humans, Male, Middle Aged, Schizophrenia, Young Adult, Clinical Trial, Journal Article",
author = "Jakobsen, {M I} and Larsen, {J R} and Svensson, {C K} and Johansen, {S S} and K Linnet and J Nielsen and A Fink-Jensen",
note = "{\circledC} 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.",
year = "2017",
month = "2",
doi = "10.1111/acps.12673",
language = "English",
volume = "135",
pages = "159--169",
journal = "Acta Psychiatrica Scandinavica",
issn = "0001-690X",
publisher = "Wiley-Blackwell Publishing Ltd",
number = "2",

}

RIS

TY - JOUR

T1 - The significance of sampling time in therapeutic drug monitoring of clozapine

AU - Jakobsen, M I

AU - Larsen, J R

AU - Svensson, C K

AU - Johansen, S S

AU - Linnet, K

AU - Nielsen, J

AU - Fink-Jensen, A

N1 - © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

PY - 2017/2

Y1 - 2017/2

N2 - OBJECTIVE: Therapeutic drug monitoring (TDM) of clozapine is standardized to 12-h postdose samplings. In clinical settings, sampling time often deviates from this time point, although the importance of the deviation is unknown. To this end, serum concentrations (s-) of clozapine and its metabolite N-desmethyl-clozapine (norclozapine) were measured at 12 ± 1 and 2 h postdose.METHOD: Forty-six patients with a diagnosis of schizophrenia, and on stable clozapine treatment, were enrolled for hourly, venous blood sampling at 10-14 h postdose.RESULTS: Minor changes in median percentage values were observed for both s-clozapine (-8.4%) and s-norclozapine (+1.2%) across the 4-h time span. Maximum individual differences were 42.8% for s-clozapine and 38.4% for s-norclozapine. Compared to 12-h values, maximum median differences were 8.4% for s-clozapine and 7.3% for s-norclozapine at deviations of ±2 h. Maximum individual differences were 52.6% for s-clozapine and 105.0% for s-norclozapine. The magnitude of s-clozapine differences was significantly associated with age, body mass index and the presence of chronic basophilia or monocytosis.CONCLUSION: The impact of deviations in clozapine TDM sampling time, within the time span of 10-14 h postdose, seems of minor importance when looking at median percentage differences. However, substantial individual differences were observed, which implies a need to adhere to a fixed sampling time.

AB - OBJECTIVE: Therapeutic drug monitoring (TDM) of clozapine is standardized to 12-h postdose samplings. In clinical settings, sampling time often deviates from this time point, although the importance of the deviation is unknown. To this end, serum concentrations (s-) of clozapine and its metabolite N-desmethyl-clozapine (norclozapine) were measured at 12 ± 1 and 2 h postdose.METHOD: Forty-six patients with a diagnosis of schizophrenia, and on stable clozapine treatment, were enrolled for hourly, venous blood sampling at 10-14 h postdose.RESULTS: Minor changes in median percentage values were observed for both s-clozapine (-8.4%) and s-norclozapine (+1.2%) across the 4-h time span. Maximum individual differences were 42.8% for s-clozapine and 38.4% for s-norclozapine. Compared to 12-h values, maximum median differences were 8.4% for s-clozapine and 7.3% for s-norclozapine at deviations of ±2 h. Maximum individual differences were 52.6% for s-clozapine and 105.0% for s-norclozapine. The magnitude of s-clozapine differences was significantly associated with age, body mass index and the presence of chronic basophilia or monocytosis.CONCLUSION: The impact of deviations in clozapine TDM sampling time, within the time span of 10-14 h postdose, seems of minor importance when looking at median percentage differences. However, substantial individual differences were observed, which implies a need to adhere to a fixed sampling time.

KW - Adult

KW - Antipsychotic Agents

KW - Clozapine

KW - Dose-Response Relationship, Drug

KW - Drug Administration Schedule

KW - Drug Monitoring

KW - Female

KW - Humans

KW - Male

KW - Middle Aged

KW - Schizophrenia

KW - Young Adult

KW - Clinical Trial

KW - Journal Article

U2 - 10.1111/acps.12673

DO - 10.1111/acps.12673

M3 - Journal article

VL - 135

SP - 159

EP - 169

JO - Acta Psychiatrica Scandinavica

JF - Acta Psychiatrica Scandinavica

SN - 0001-690X

IS - 2

ER -

ID: 52615546