Urinary screening for alpha-OH triazolam by FPIA and EIA with confirmation by GC/MS

Triazolam is a very short-acting triazolobenzodiazepine with sedative-hypnotic properties. Approximately 2% of an oral dose is excreted unchanged in the urine. The major urinary metabolite is alpha-hydroxytriazolam glucuronide (70% of the dose). The objective of this study was to characterize the reactivity of alpha-hydroxytriazolam in the urine benzodiazepine assay by fluorescence polarization immunoassay (FPIA; Abbott TDx) in comparison with enzyme immunoassay (EIA; Syva EMIT d.a.u. benzodiazepine assay). alpha-OH triazolam at 300 ng/mL gave a response equivalent to the 200-ng/mL nordiazepam Abbott calibrator. In the EMIT assay, alpha-OH triazolam gave a response equivalent to the 300-ng/mL calibrator (Syva) at 100-200 ng/mL. Both immunoassays gave positive results in 9 out of 9 urine specimens collected from individuals receiving triazolam. Confirmation was performed by analyzing for alpha-OH triazolam after enzymatic hydrolysis and formation of a TMS derivative for GC/MS. All urine specimens were positive for alpha-OH triazolam. In conclusion, both the FPIA and EIA immunoassay screening assays are acceptable for detecting the presence of alpha-OH triazolam in the urine of patients receiving therapeutic doses of triazolam.