How Long can a Human Stay Awake?

How long can a human body stay awake all depends on the activity of the human while being awake, if the human is conserving energy by resting they would be able to stay awake longer than another person. Typically a human can stay up for 3 to 5 days before they begin drifting slowly into sleep and hallucinating. It is not healthy to stay up to long because your body needs the sleep to stay healthy and work properly.