Midazolam is a short-acting benzodiazepine with anxiolytic, sedative-hypnotic and marked amnestic properties. Due to an excellent local tolerability, its slight reduction in blood pressure and minor dose-related respiratory depression, midazolam is useful for anaesthetic induction and postoperative (long-term) sedation especially for intensive care patients. Compared to other benzodiazepines, midazolam exhibits a rapid onset of action and a fast hepatic elimination (t1/2 2 to 4h; CL 400 to 600 ml/min). In patients with liver cirrhosis and critically ill patients, an impaired elimination and longer duration of action has to be taken into consideration. Likewise, in the elderly an amplified response will be noted, because of the increased sensitivity of the central nervous system to benzodiazepines during aging. In such populations at risk, "normal" dosage of midazolam has to be reduced at least by factor 2.