Triflubazam is a 1,5-benzodiazepine derivative. The hypnotic activity of the 1,5-benzodiazepines is limited, and that this is particularly so in the case of triflubazam. Subjects reported impaired sleep with triflubazam (40 mg), and a sense of less wakefulness the morning. The effect of triflubazam may have persisted beyond the night of ingestion. No effect of triflubazam was observed on total sleep time, stage shifts in the first 6 h or latency to the first rapid eye movement period of sleep. Triflubazam has psychopharmacological properties in animals suggestive of antianxiety activity of a longer duration than that of diazepam. The metabolism of triflubazam by man is characterized by extensive N-demethylation, aromatic hydroxylation, aromatic O-methylation and dihydrodiol formation.