Ambien is the brand name for a medication called zolpidem, which is a sedative-hypnotic primarily used to treat insomnia. It belongs to a class of drugs known as non-benzodiazepine hypnotics. Zolpidem works by affecting certain chemicals in the brain that may be unbalanced in people with sleep problems. It enhances the activity of gamma-aminobutyric acid (GABA), a neurotransmitter that inhibits brain activity, leading to a calming effect.