Elimination of 7-aminoflunitrazepam and flunitrazepam in urine after a single dose of Rohypnol (R)

The hypnotic benzodiazepine flunitrazepam (Rohypnol(R)) has been identified as the drug of choice for the purposes of "drugging" unsuspecting victims and raping them while they are under the influence of this substance. The o bjective of this paper was to study elimination of flunitrazepam and 7-amin oflunitrazepam in urine collected from ten healthy volunteers who received a single 2 mg oral dose of Rohypnol(R), to determine how long after drug ad ministration 7-aminoflunitrazepam can be detected. A highly sensitive NCI-G C-MS method for the simultaneous quantitation of flunitrazepam (LOQ 100 pg/ mL) and 7-aminoflunitrazepam (LOQ 10 pg/mL) in urine was developed. All sam ples were screened for benzodiazepines using optimized micro-plate enzyme i mmunoassay. The highest concentrations of 7-aminoflunitrazepam (70-518 ng/m L) and flunitrazepam (0.7-2.8 ng/mL) in urine were observed 6 h after drug administration in nine subjects and after 24 h in one subject. In six subje cts 7-aminoflunitrazepam was detected up to 14 days after flunitrazepam adm inistration, in one subject up to 21 days and in three subjects up to 28 da ys. In urine samples collected from six volunteers, flunitrazepam was detec ted three days after Rohypnol(R) intake, in three subjects 24 h, and in one subject 5 days later. Benzodiazepine micro-plate enzyme immunoassay kit al lowed the detection of flunitrazepam and metabolities 5 to 21 days after dr ug administration.