Ambien (zolpidem) is a medicine that is primarily used to treat insomnia by providing quicker sleep. In the US, Ambien is classified as a Schedule IV controlled substance and is also approved by the FDA. Ambien’s main purpose is to cure insomnia, which is characterized by difficulty sleeping and staying asleep, temporarily. Ambien functions by amplifying the effects of gamma-aminobutyric acid (GABA), a neurotransmitter in the brain