Anxiety and sleep after fosazepam.

1 Six volunteers of mean age 59 years received placebo for week, then fosazepam (60 mg) nightly for 3 weeks, then placebo for 3 weeks. Subjective ratings and all-night electrophysiological recordings were made. 2 Fosazepam administration improved subjective sleep quality nut impaired feelings of morning vitality. Its withdrawal was associated with anxiety, impaired concentration and continuing impairment of morning vitality. Measured sleep duration increased on fosazepam, sleep was less broken, slow wave sleep stages 3 and 4 diminished in duration and so did REM sleep. 3 Despite the short-life of fosazepam some drug effects persisted for several days after withdrawal, suggesting action of a long half-life metabolite.