title: Liquid-chromatographic assay of diazepam and its major metabolites in serum, and application to pharmacokinetic study of high doses of diazepam in schizophrenics.
abstract: In this rapid, sensitive method for simultaneously determining diazepam and its biologically active metabolites--nordiazepam, oxazepam, and temazepam--in serum, 250 to 1000 microL of serum is extracted with ether and the extracted compounds are quantified by "high-performance" liquid chromatography on a Shimpack FLC-C8 microparticulate column. Absorbance of the effluent is monitored at 254 nm. The limit of detection in serum is about 10 micrograms/L for each drug. Analytical recovery of each drug added to the serum varied from 91 to 102% for oxazepam and temazepam, from 82 to 99% for nordiazepam and diazepam. Within-day and between-day CVs ranged from 2 to 5% for oxazepam and temazepam, and from 2 to 7% for nordiazepam and diazepam. We also report results on using this assay in a pharmacokinetic study of high doses of diazepam used to treat chronic schizophrenic patients.
mesh_terms: D000284:Administration, Oral; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003975:Diazepam / Q000008:administration & dosage / Q000097:blood* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007700:Kinetics; D003708:Nordazepam / Q000097:blood; D010076:Oxazepam / Q000097:blood; D012559:Schizophrenia / Q000188:drug therapy*; D013693:Temazepam / Q000097:blood
chemical_list: D003708:Nordazepam; D010076:Oxazepam; D013693:Temazepam; D003975:Diazepam