Ambien CR

Zolpidem (sold under the brand names Ambien, Ambien CR, Stilnox, and Sublinox) is a prescription medication used for the treatment of insomnia and some brain disorders. It is a short-acting nonbenzodiazepine hypnotic of the imidazopyridine class that potentiates gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter, by binding to GABA_A receptors at the same location as benzodiazepines. It works quickly, usually within 15 minutes, and has a short half-life of two to three hours.

Zolpidem has not adequately demonstrated effectiveness in maintaining sleep, unless delivered in a controlled-release (CR) form. However, it is effective in initiating sleep. Its hypnotic effects are similar to those of the benzodiazepine class of drugs, but it is molecularly distinct from the classical benzodiazepine molecule and is classified as an imidazopyridine. Flumazenil, a benzodiazepine receptor antagonist, which is used for benzodiazepine overdose, can also reverse zolpidem's sedative/hypnotic and memory-impairing effects.

As a muscle relaxant and anticonvulsant, the drug's effects are not evident until dosages 10 and 20 times those required for sedation, respectively, are reached. For that reason, zolpidem has never been approved for either muscle relaxation or seizure prevention. Such drastically increased doses are also more inclined to induce one or more of the drug's adverse side effects, including hallucinations and amnesia.

The patent in the United States on zolpidem was held by the French pharmaceutical corporation Sanofi-Aventis. On April 23, 2007, the U.S. Food and Drug Administration (FDA) approved 13 generic versions of zolpidem tartrate. Zolpidem is available from several generic manufacturers in the UK, as a generic from Sandoz in South Africa and TEVA in Israel, as well as from other manufacturers such as Ratiopharm (Germany).

On January 10, 2013, the Food and Drug Administration announced it is requiring the manufacturer of Ambien and Zolpimist to cut the recommended dosage in half for women after laboratory studies showed that the medicines can leave patients drowsy in the morning and at risk for car accidents.