Comparison of midazolam and triazolam for residual effects.

A comparison of midazolam (Ro 21-3981, Dormicum) and triazolam was performed with respect to residual effects 7 h after administration. A preliminary study was conducted in 25 trainee pilots attending the Swiss Civil Aviation School, followed by the main study in 105 pilots of the Swissair DC-9 fleet. All subjects were volunteers. Performance was measured in objective terms with the Instrument Coordination Analyser (ICA) which is used for the selection of trainee pilots. The subjects assessed their sleep and condition on waking by means of a questionnaire. In the double-blind trial each subject received either 0.5 mg triazolam or 15 mg midazolam or placebo. The medication was taken at midnight; the test was performed at 7 a.m. The preliminary study was conducted to assess the suitability of the test equipment. Results of the main study: With 15 mg midazolam no residual effects were detectable 7 h after administration (difference from placebo not statistically significant). Triazolam 0.5 mg, on the other hand, produced a statistically significant impairment of performance. The frequency of side effects was significantly greater under triazolam 0.5 mg than under midazolam 15 mg or placebo, whereas there was no difference between midazolam 15 mg and placebo (p = 0.49).