Zolpidem has not adequately demonstrated effectiveness in maintaining sleep; 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 an anticonvulsant and muscle relaxant, the beneficial effects start to emerge at 10 and 20 times the dose required for sedation, respectively. For that reason, it has never been approved for either muscle relaxation or seizure prevention. Such drastically increased doses are more inclined to induce one or more negative side-effects, including hallucinations and amnesia.
Zolpidem is one of the most common GABA-potentiating sleeping medications prescribed in the Netherlands, with a total of 582,660 prescriptions dispensed in 2008. 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, TEVA in Israel, as well as from other manufacturers such as Ratiopharm (Germany).