Ambien is a hypnotic drug that has direct effects on the central nervous system, specifically the brain. Ambien drug causes drowsiness and is safe and effective for initiating and maintaining sleep. Ambien tablet contains Zolpidem Tartrate as its active ingredient. Generic Ambien is used to treat insomnia or acute insomnia. You can order Ambien online from any reliable site that is medically tested. Take Ambien medicine orally as directed by your doctor, on an empty stomach, usually once at night. Since Zolpidem is working quickly, take it right before you get to bed. Don't take Ambien pill with or after a meal, because it won't work as quickly.