Describe Ambien. A sedative sometimes known as a hypnotic, Ambien is. Ambien (zolpidem) alters brain chemicals that may be out of balance in those who have insomnia. Insomnia is treated with ambien. When you first get into bed, the immediate-release tablet is utilised to aid in sleep. Ambien CR, an extended-release version, includes two layers: one that dissolves quickly to aid in falling asleep and the other that dissolves more gradually to aid in maintaining sleep. Which form of Ambien is most suitable for you will be decided by your doctor.