Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (1203 page)

   Extracted in alkaline liquid–liquid or solid-phase extraction scheme

   GC/MS (SIM) due to low concentrations difficult to observe in full scan mode; LC/MS

   Active metabolite 1-(2-pyrimidinyl)piperazine (1-PP) may also be measured

   Limit of quantitation: 1 ng/mL

   
Zolpidem

   Structurally similar to benzodiazepines

   No specific immunoassay-based screening tests available for clinical use (recently available for forensic applications)

   Readily extracted in alkaline liquid–liquid or solid-phase extraction scheme

   Gas chromatography, liquid chromatography, GC/MS, LC/MS

   Limit of quantitation: 10–50 ng/mL

   
Zopiclone

   Newer hypnotic

   No immunoassay-based screening tests currently available for clinical use