[Assessment of the efficacy and tolerance of a benzodiazepine antagonist (Ro 15-1788)]

The aim of this study was to evaluate the efficacy and the tolerance of Ro 15-1788, a specific benzodiazepine antagonist, in reversing the effects of midazolam. Six healthy male volunteers (mean age 32 +/- 3 years; mean weight 75.5 +/- 5 kg) took part in this study. Two of the three following drugs: midazolam (0.15 mg X kg-1), Ro 15-1788 (0.1 mg X kg-1) or placebo, diluted in 10 ml isotonic saline, were injected intravenously in 15 s at 5 min intervals in a double-blind manner in each subject during six randomized sessions: midazolam-placebo; Ro-placebo; placebo-midazolam; placebo-Ro; midazolam-Ro; Ro-midazolam. At least four days were allowed between each session for each subject. The evaluation of the effects on the central nervous system was as follows. At the time of injection of the first drug and, if possible, at the time of injection of the second drug, the subject was asked to count aloud to 150. The following variables were timed: start of dysarthria, cessation of counting, abolition and duration of absence of the ciliary reflex and duration of induced sleep. Retrograde and anterograde amnesia were evaluated by the recall of a playing card and a number. Haemodynamic effects (variations of systolic and diastolic pressures and pulses rate) as well as respiratory ones (apnoea) were also studied.(ABSTRACT TRUNCATED AT 250 WORDS)