Aims: An objective physiological test was used to investigate the hangover effect, its time course and dose relationship compared to placebo and an herbal relaxant.
Methods: Pupillographic Sleepiness Test as an objective measurement, Stanford Sleepiness Scale (SSS) and visual analogue scales (VAS) were used. Study design included: (a) randomised, double-blind, double-dummy, placebo-controlled crossover trial; (b) double-blind, placebo-controlled, randomised study. Primary end point was the Pupillary Unrest Index (lnPUI).
Results: Oxazepam 10 mg did not increase PUI. In the VAS and SSS, there was no increase in sleepiness after the three treatment periods. Neither 10 nor 30 mg oxazepam caused sedation in healthy volunteers. Subjective and objective sleepiness measures correlated significantly.
Discussion: The lack of sedative effects after vespertine intake of oxazepam (10/30 mg) seems to be relevant with respect to product safety. With regard to the subjective perception at 30 mg, fatigue rather than sleepiness may be the underlying reason.