In our article on Drugs for Chronic Insomnia, we said there is little evidence that antidepressants such as trazodone, mirtazapine, or amitriptyline are effective in treating insomnia not associated with depression. We received a comment from a reader who has prescribed the tricyclic antidepressant amitriptyline for insomnia, particularly for patients with headache disorders, and finds that most patients are satisfied with the treatment.

Propofol (Diprivan - Stuart), a new intravenous (IV) sedative-hypnotic, was recently marketed in the USA for induction of anesthesia, or for maintenance of general anesthesia as part of a balanced anesthesia regimen. Older drugs used in a similar way include thiopental (Pentothal; and others) and midazolam (Versed).

Desflurane (Suprane - Anaquest), an inhalation anesthetic, has been approved by the US Food and Drug Administration for induction and maintenance of general anesthesia in adults and for maintenance of anesthesia in infants and children. Like isoflurane (Forane), the last volatile anesthetic to become available in the USA (Medical Letter, 23:112, 1981), the new agent is a halogenated methyl ethyl ether, differing from isoflurane in the substitution of a fluorine for a chlorine atom.

Gamma hydroxybutyrate (GHB), a central-nervous-system depressant notorious for its use in "date rape", was approved by the FDA in 2002 as sodium oxybate (Xyrem - Jazz Pharmaceuticals) for oral treatment of cataplexy in patients with narcolepsy. Now it has also been approved for treatment of excessive daytime sleepiness (EDS) in these patients. Xyrem is a Schedule III controlled substance.

The FDA has approved the melatonin receptor agonist tasimelteon (Hetlioz – Vanda) for treatment of non-24-hour sleep-wake disorder (non-24), which is common in totally blind persons. Tasimelteon is the first drug approved for this indication and the second melatonin receptor agonist approved for use in the US; ramelteon (Rozerem) was approved earlier for treatment of insomnia. Melatonin itself has not been approved by the FDA for any indication; it is available in the US as a dietary supplement and is promoted as a sleep aid.

The FDA has approved the marketing of an extended-release formulation of trazodone (Oleptro – Angelini Labopharm) for treatment of major depressive disorder in adults. Immediate-release trazodone has been available for treatment of depression for many years, but is used mostly in low doses for its sedating effects.

Xerostomia, dry mouth due to decreased or absent saliva, is a common problem, particularly among elderly patients. Decreased salivary flow can be due to many different conditions, including drug therapy, Sj gren's syndrome (keratoconjunctivitis sicca) or radiation of the salivary glands.

Over-the-counter products containing melatonin are widely used as sleep aids in children and adults.

Tramadol hydrochloride (Ultram - Ortho-McNeil), a centrally-acting analgesic marketed in Germany since 1977, was recently approved by the US Food and Drug Administration for oral treatment of moderate to moderately severe pain. Despite some opioid activity, tramadol has not been scheduled as a controlled substance.

Advertisements for clemastine (Tavist-1 - Sandoz), an ethanolamine oral antihistamine, have recently appeared on television and in major newspapers in the USA. Clemastine is an old drug (Medical Letter, 21:24, 1979) that has now become available without a prescription.