ABSTRACT
A wide range of substances have been recommended for the treatment of insomnia over the past several centuries. Although many of these have been efficacious in improving sleep, they have been accompanied by serious safety problems. Opium-based preparations predominated during the 18th and 19th centuries. Chloral hydrate use dates back to the mid 1800s. During the first half of the 20th century barbiturate and related medications were commonly prescribed. In the 1960s and 1970s, benzodiazepine hypnotics became available and were the primary insomnia medications. Among these have been estazolam, flunitrazepam, flurazepam, loprazolam, lormetazepam, nitrazepam, quazepam, temazepam, and triazolam. Selected benzodiazepine hypnotics remain available, but play a less prominent role in the treatment of insomnia. These hypnotics vary considerably in pharmacological properties, with a major effect on the duration of action. Various benzodiazepines not indicated or licensed for insomnia continue to be prescribed for insomnia. Characteristics that have limited benzodiazepine use include concerns about tolerance, withdrawal, abuse liability, labeling restrictions, and, with longer half-life medications, the potential for residual daytime effects.1
