POSTMORTEM DISTRIBUTION AND REDISTRIBUTION OF NITROBENZODIAZEPINES INMAN

The distribution of the nitrobenzodiazepines, flunitrazepam, clonazepa m and nitrazepam, and their respective 7-amino metabolites were examin ed in blood, serum, vitreous humor, liver, bile and urine of decedents taking these drugs. Peripheral blood, serum and liver concentrations were not significantly different to each other. However, vitreous conc entrations were one-third of blood, while bile concentrations were 5-1 2 fold higher. Blood, serum and vitreous contained predominantly the 7 -amino metabolite, liver contained only the metabolite, while bile con tained significant concentrations of both the parent drug and the 7-am ino metabolite. Urine contained only small concentrations of parent dr ug, however, as expected a number of metabolites were detected. Redist ribution studies compared the drug concentrations of femoral blood, ta ken at body admission to the mortuary, with femoral blood taken at aut opsy approximately 39 h later in 48 cases. The concentrations of 7-ami no metabolites were not significantly different, however the concentra tions of parent nitrobenzodiazepines were significantly higher in the admission specimens. In 6 cases in which subclavian blood was taken, t he concentrations were not significantly different to the concentratio ns in admission blood. Similar findings were observed when femoral and subclavian blood concentrations were compared in 6 cases. There was a lso no apparent difference in total blood concentrations of nitrobenzo diazepines when blood concentrations taken in hospital shortly prior t o death were compared to postmortem blood. Postmortem diffusion into p eripheral blood is therefore not a confounding factor in the interpret ation of nitrobenzodiazepine concentrations.