Methodology for demonstrating sustained efficacy of hypnotics: a comparative study of triazolam and flurazepam.

To test for sustained hypnotic efficacy, triazolam (0.6 mg) or flurazepam (30 mg) was given to chronic insomniac patients for 7 consecutive nights in parallel, double-blind design. Triazolam at this dose was an effective hypnotic by all usual subjective measures and did not produce appreciable hangover. Flurazepam performed similarly. For either drug, comparison of the mean scores for the first 2 nights with that for the last 2 nights for any of the parameters did not reveal any significant difference. Thus, both triazolam and flurazepam showed sustained efficacy for 1 week at these doses. Some interesting theoretical and practical questions about the measurement of sustained efficacy of hypnotics in situations of repetitive dosing were addressed by the study. While a placebo control is desirable, the results obtained may be uninterpretable. An acute-care hospital setting may not be the ideal setting for doing such studies. There were indications from the study that the first-night results in a hypnotic clinical trial may be atypical.