Evaluation of the efficacy of metaclazepam and its effects on sleep, psychomotor performance and cognitive function in anxious patients

The effects of single and multiple doses of metaclazepam were investigated in 60 anxious patients. A 15 mg nocturnal dose of metaclazepam was compared to two daily doses (5 mg in the morning and 10 mg at bedtime) in terms of efficacy and effects on various aspects of sleep, cognitive function and psychomotor performance. Anxiolytic efficacy was assessed by means of questionnaires, including the Self Rating Anxiety Scale of Zung, State Trait Anxiety Inventory of Spielberger, and a modified version of the Hamilton Anxiety Rating Scale. Hypnotic activity was evaluated using a clinical rating of insomnia questionnaire. The psychometric battery consisted of tests of Critical Flicker Fusion, Choice Reaction Time and Digit Span. In terms of clinical efficacy, metaclazepam administered in either dosage regimen demonstrated a good anxiolytic activity profile. Both dosage regimens were effective in improving the quality and quantity of sleep, however the number of intermittent awakenings were significantly higher with the daily divided dose. In addition, the nocturnal administration of metaclazepam did not appear to be associated with any undesirable side effects or decrements in psychomotor performance the following morning. In conclusion, it appears that a 15 mg bedtime dose of metaclazepam is efficacious in relieving anxiety without impairing psychomotor performance the following morning. (C) 1998 John Wiley & Sons, Ltd.