Three benzodiazepines and 16 other compounds are marketed in the USA for treatment of insomnia. Many authorities believe that insomnia is overdiagnosed and overtreated (MK Erman, ed, Sleep Disorders, Psychiatr Clin North Am, Volume 10, Dec 1987).

Quazepam (Doral - Baker Cummins, Wallace) is a trifluoroethyl benzodiazepine made by Schering and approved in 1985 by the US Food and Drug Administration for treatment of insomnia. Like other benzodiazepines, it is a Schedule IV controlled substance.Quazepam (Doral - Baker Cummins, Wallace) is a trifluoroethyl benzodiazepine made by Schering and approved in 1985 by the US Food and Drug Administration for treatment of insomnia. Like other benzodiazepines, it is a Schedule IV controlled substance.

Eszopiclone (Lunesta - Sepracor), a benzodiazepine-like drug, has been approved by the FDA for oral treatment of insomnia. It is the S-isomer of zopiclone (Imovane, and others in Canada), which has been available in other countries for almost 20 years. Unlike similar drugs such as zolpidem (Ambien) or zaleplon (Sonata), Lunesta is not being restricted in its labeling to short-term use. Like other hypnotics, eszopiclone is a schedule IV drug.

Estazolam (ProSom - Abbott), a triazolobenzodiazepine derivative similar in structure to alprazolam (Xanax) and triazolam (Halcion), was recently marketed in the USA for treatment of insomnia.

Zolpidem (Ambien - Sanofi-Aventis), a nonbenzodiazepine benzodiazepine receptor agonist, is the most frequently prescribed hypnotic in the US. As its patent approaches expiration, its manufacturer has received FDA approval to market an extended-release formulation of the drug, Ambien CR. The pharmacological rationale for doing so is that short-acting hypnotics like zolpidem are more effective at inducing sleep than they are at maintaining it.

Cognitive behavioral therapy for insomnia (CBT-I) is recommended for initial treatment of chronic insomnia. CBT-I includes stimulus control, sleep education and hygiene, sleep restriction, relaxation training, and cognitive therapy. When CBT-I alone is not effective, pharmacologic treatment should be added.

Ramelteon (Rozerem - Takeda), a melatonin receptor agonist, has been approved by the FDA for treatment of insomnia characterized by difficulty falling asleep. Unlike all other prescription hypnotics, which are classified as schedule IV drugs, ramelteon is not a controlled substance.

The FDA has approved suvorexant (Belsomra – Merck), the first orexin receptor antagonist to become available in the US, for treatment of sleep-onset and/or sleep-maintenance insomnia.

Zolpidem oral spray (Zolpimist – NovaDel/ECR), a new formulation of the oral hypnotic zolpidem tartrate (Ambien, and others), has been approved by the FDA for short-term treatment of insomnia characterized by difficulty falling asleep.

The FDA has approved a new low-dose formulation of the tricyclic antidepressant doxepin (Silenor – Somaxon) for treatment of insomnia associated with sleep maintenance. The manufacturer claims that this dose retains the hypnotic effect of doxepin, without typical tricyclic adverse effects. Doxepin is available generically in higher-strength capsules and in a liquid formulation.