text: why am i prepetually drowsy? i am 20 years old and cannot keep my eyes open during the day. i normalyy get about 9-10 hours of sleep a night. some days when i only get say around 7, as soon as i get home fro an outing, i have to sleep straightaway. i remember i was a little like this in my mid teens. is this like a growing phase? you may not be getting the right amount of sleep. one reason for that may be that you are tossing and turning all night. (mattress, eating late, stress...)  it may be that you are lacking nutritionally. too many carbs, vitamins, minerals...   not enough water.  too much caffeine my also be dehydrating you. smoking?  lack of exercise.  mild depression. hope that helped