Self-reports of anxiety level and EEG changes after a single dose of benzodiazepines: Double-blind comparison of two forms of oxazepam

A new formulation of oxazepam especially designed to increase the speed of absorption and eliminate the need to use water (freeze-dried dosage formulation; FDDF) was compared in double-blind and crossover conditions with the standard tablets of the same compound. 5 inpatients with generalized anxiety disorder received at 1-week intervals a single 30 mg dose of one of the compounds. Every 8 min for 96 min after drug intake, they completed a battery of visual analogue scales and had an EEG recording with computerized spectral analysis. Results showed a significantly more rapid onset of activity of FDDF oxazepam for both the self-reports of anxiety level (p < 0.005) and the specific β2 EEG changes (p < 0.0001), which were significantly correlated (r = -0.73; p < 0.01). Moreover, all patients rated FDDF oxazepam as having faster onset of action in clinical change than regular tablets (p < 0.05). This study shows the value of visual analogue scales, pharmaco-EEG, and crossover design in well-selected anxious inpatients in substantiating clinical differences between anxiolytic pharmacotherapies. © 1984 S. Karger AG, Basel.