How come i have to be a certain age to buy 6 hour energy?

Age limits: Despite what the advertising will lead you to believe, these products contain drugs - mainly caffeine. Caffeine in children and adolescents whose systems are not fully developed yet can cause problems - heart arrhythmias, headaches, tremors and shakes, seizures. I had a 17 y/o in my practice who had two seizures after popping a few 6-hours and not sleeping all night. It just is not worth the risk!