Ambien (zolpidem) is a prescription medication used to help people with insomnia fall and stay asleep. It belongs to a class of drugs called sedative-hypnotics, which work by slowing down brain activity to promote sleep. Ambien is available in both immediate-release and extended-release forms, with the former helping users fall asleep faster and the latter helping maintain sleep through the night. It's typically prescribed for short-term use (often two weeks or less) to minimize the risk of dependency.