Ambien is a sedative-hypnotic drug that is prescribed to treat insomnia. Similar to drugs like Lunesta and Sonata, Ambien is designed to be a temporary sleep aid and is not meant to be taken on a long-term basis. Although it is marketed as being a less-addictive and habit-forming drug than many benzodiazepines, Ambien users may still become dependent and addicted to the drug.