Quazepam is a benzodiazepine hypnotic that can be useful in the adjunctive pharmacologic treatment of insomnia. It is slowly eliminated due to the long elimination half-lives of the parent compound and its two active metabolites, 2-oxoquazepam and N-desalkyl-2-oxoquazepam. This drug is recommended in doses of 15 mg for adults and 7.5 mg for geriatric patients. Sleep laboratory studies and clinical trials have shown that the 15 mg dose is quite efficacious for inducing and maintaining sleep not only with initial and short-term use but also with continued use. The 7.5 mg dose which has been studied less extensively has also been shown to be effective for inducing and maintaining sleep. There is considerable evidence of carryover effectiveness both during drug administration and after withdrawal. Thus, rebound phenomena are not observed during administration (early morning insomnia and daytime anxiety) and after withdrawal (rebound insomnia). Furthermore, certain behavioral side effects that have occurred with certain benzodiazepines (triazolam) have not been reported with quazepam. The only notable side effect seen with quazepam is a variable degree of daytime sedation, which can be minimized by intermittent use of the 15 mg dose when necessary and use of the 7.5 mg dose in the elderly. In comparison to triazolam and temazepam, quazepam is more effective with short-term use, and with continued use it maintains its efficacy in contrast to both of these drugs which show rapid development of tolerance. Most important, quazepam lacks the frequent and severe side effects increasingly reported with triazolam use or following its withdrawal.