Melatonin
"I am a 13 year old boy and I take melatonin because I got a concussion but couldn't fall asleep and couldn't stay asleep. But then I took  melatonin and went asleep easier and was able to stay asleep. The only this that bothers me is that I can't sleep without it now. I could lay in bed for hours and not sleep. I take 3 milligrams of melatonin each night (prescribed by my doctor)."