Acute effects of two dosages of orally administered midazolam on psychomotor performance in healthy volunteers.

The acute effects of two doses of orally administered midazolam (Dormicum, 10 and 30 mg) which as a putative anaesthetic premedicant is clinically expected to provide valid effects already after acute dosing on sedation parameters, were evaluated vs placebo within a randomized double-blind 3-period crossover design in 12 healthy male volunteers. The washout period was 7 days. Objective sedation measures were obtained with the oculodynamic test (ODT), which is a multidimensional computerized psychological testing device. Cardiorespiratory parameters were simultaneously sampled throughout the ODT-sessions. Intradiurnal assessments were done at -30, +30, +90 and +180 min post-dose. Subjective side effects were recorded by spontaneous recall and by means of a symptom check list. With midazolam there was a dose-dependent increase of sedation in the ODT, which persisted for at least 3 h after intake. The subjective side effects fitted a sedative pattern with mild (10 mg) and marked (30 mg) impairment of vigilance. Cardiovascular and respiratory parameters were changed vs placebo. All subjects reported an anterograde amnesia after the 30-mg dose at about 3 or 5 h post-dose, which depicts a double-peaking time course in some subjects. The subjects ability to cooperate in the psychomotor test regimen was distinctly impaired after 30 mg of midazolam during daytime administration.