Schizophrenia
Conditions
Keywords
Schizophrenia, Clozapine, TDM, Serum Concentration
Brief summary
The role of Therapeutic Drug Monitoring (TDM) in clozapine dose adjustment have been debated. Blood samples for s-clozapine monitoring should be drawn 12 hours post dose. The scope of this trial is to describe changes of s-clozapine and s-N-desmethyl-clozapine within the range of 10-14 hours after the last administration of clozapine .
Detailed description
Several factors can influence s-clozapine and thereby the occurence of dose-related adverse reactions and level of treatment response. The role of Therapeutic Drug Monitoring (TDM) in clozapine dose adjustment have been debated. Blood samples for s-clozapine monitoring are recommended to be drawn 12 hours post dose. Uncertainty regarding the timing of blood sampling and the individual pharmakokinetics for clozapine +/- 2 hours from the 12-hour timepoint, leads to uncertainty regarding the comparability of serum concentrations and the information hold within them. The scope of this trial is to describe changes of s-clozapine and s-N-desmethyl-clozapine within the range of 10-14 hours after the last administration of clozapine . In addition we want to investigate if any of the following covariates might affect the change of s-clozapine and s-N-desmethyl-clozapine: Sex, age, BMI, co-medications, signs of infection, caffeine intake and smoking.
Interventions
PROCEDUREBlood sampling
blood samples for s-clozapine and s-desmethyl-clozapine analysis are collected at 10, 11, 12, 13 and 14 hours post evening-clozapine-administration
DRUGClozapine
Registration of the exact time of drug administration. Also postponement of any morning clozapine administration until ended blood sampling.
Sponsors
University of Copenhagen
Rigshospitalet, Denmark
Anders Fink-Jensen, MD, DMSci
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 64 Years
Healthy volunteers
No
Inclusion criteria
* Age 18 \< 65 * Diagnosed with schizophrenia according to the criteria of ICD10 (International Classification of Diseases, World Health Organization) or the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, the American Psychiatric Association) * Unchanged dose of clozapine for the last 30 days * Usual time of clozapine evening-dose administration between 9 and 12 pm.
Exclusion criteria
* Significant drug or alcohol abuse that affects participation in this trial * Non- or partial compliance of clozapine the day before the trial (assessed by interview) * Unresponsive by telephone the evening before the trial * Consumption of clozapine in the morning on the day of the trial * Significant change in smoking habits within the last 30 days (assessed by interview) * Significant change of caffeine intake within the last 7 days (assessed by interview) * Modified use of other antipsychotics within the last 30 days * Within the last 30 days (7 days for hormone based contraceptives) changes in the use of other medications that can affect s- clozapine during the trial : ( fluvoxamine, ciprofloxacin, hormone based contraceptives, carbamazepine , phenytoin , rifampicin, omeprazole ) * Females who are pregnant or breast-feeding
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Percentage change in serum-clozapine | 10 - 14 hours post drug administration |
Secondary
| Measure | Time frame |
|---|---|
| Percentage change in serum-clozapine (multiple shorter ranges) | < 10 -14 hours post dose |
Countries
Denmark
Outcome results
None listed