[Relationship between clinical effects and pharmacokinetics of midazolam on i.m. and i.v. application to volunteers/1st comm.: Clinical aspects (author's transl)].

The onset of action of 8-chloro-6-(2-fluorophenyl)-1-methyl-4H-imidazo [1,5-a] [1,4] benzodiazepine (midazolam, Ro 21-3981, Dormicum), after i.v. injection of 12.5 mg, occurs towards the end of the injection and reaches its maximum level in about 3 min. After i.m. injection, the first effects are generally seen about 5 min later. The maximum effect is reached in about 20 min. Psychometric tests tend to return to normal within 2 h after the injection and are completely normalized within 4 h. Although no objective effect was measurable, the subjects sometimes reported subjective effects lasting up to 6 h. These were mainly signs of mild residual fatigue. The objective and subjective symptoms disappeared after 6 h. General and local tolerance was excellent. A transient sensation (lasting a few minutes) of slight burning was mentioned by some subjects after i.m. injection. Midazolam is therefore a sleep-inducing agent distinguished by rapid and regular onset of action, relatively short duration of action and a low incidence of side effects.