Therapeutic drug monitoring
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Immunoassays designed to detect use of older benzodiazepines such as oxazepam or diazepam often cannot detect triazolam use because of the low doses of triazolam administered, rapid biotransformation to metabolites with poor cross-reactivities, and the small amount of alpha OH triazolam glucuronide excreted in the urine. Previous studies have demonstrated that certain immunoassays have high cross-reactivity to alpha OH triazolam but are unable to detect therapeutic triazolam use in urine. ⋯ With a 200 ng/ml cut-off, 4/30 of the urine specimens screened positive for benzodiazepines without enzymatic hydrolysis and 6/30 after enzymatic hydrolysis. When using an in-house 100 ng/ml nitrazepam cut-off calibrator, 10/30 urine specimens were positive in the reformulated CEDIA assay without hydrolysis and 22/30 were positive with enzymatic hydrolysis before screening.