Prolonged excretion of 7-aminoclonazepam in urine after repeated ingestion of clonazepam: a case report.

Urinary analyses of the metabolite 7-aminoclonazepam (7-AC) can be helpful in monitoring drug abuse and in the context of suspected drug-facilitated sexual assaults (DFSA). Only two studies have reported detection times of 7-AC in urine after a single dose of clonazepam, and no previous studies have reported detection times after repeated ingestions of clonazepam. This report describes along detection time of 7-AC in urine in the case of a 28-year-old woman with a two year history of daily drug abuse of heroin and clonazepam, who was admitted to a detoxification unit. Urinary samples were delivered every morning for 9 days. Screening analysis in urine was performed by immunoassay, and confirmation analysis by LC-MS/MS. 7-AC was detected for 9 days, and the concentration at day 9 was still high (97 ng/ml), compared to previously reported data. These results indicate that after repeated ingestions of clonazepam, 7-AC can possibly be detected for about 2-3 weeks after cessation, applying cut-off levels commonly used in drug testing programs and DFSA cases.