Flunitrazepam and lormetazepam do not affect the pharmacokinetics of the benzodiazepine antagonist Ro 15-1788.

Following a single intravenous dose of 0.1 mg/kg, the pharmacokinetics of Ro 15-1788, a specific benzodiazepine antagonist, have been investigated in 20 healthy male volunteers. In random order injection of Ro 15-1788 has been preceded (5 min) by intravenous dosing with 0.06 mg/kg of lormetazepam (n = 6), 0.03 mg/kg of flunitrazepam (n = 8) or placebo (n = 6). The rapid elimination of the antagonist could be characterized by an elimination half-life between 0.9 to 1.4 h and a total plasma clearance of 727 to 1440 ml/min. These single dose studies indicate that the disposition of Ro 15-1788 was not affected by the acute coadministration of both benzodiazepines.