Why can't I sleep at night?

[Spiget]

For most of my life I haven't been able to fall asleep easily at night.  Why?  I mean, I can fall asleep in cars(not while I'm driving), chairs, I've even fallen asleep standing up once, but when I'm laying in bed I just don't sleep.  On average I get about 3-4 hours of sleep and I almost never fall asleep before 1a.m.  sometimes as late as 3.  This posses a problem because I have to get up on the weekdays at 4:30 to get to work on time.  I'm sluggish and tired throughout the day, but at night I'm wide awake and restless.  It's gotten so bad that I end up reading a book until I'm to exhausted to even keep my eyes open.  Can someone tell me why I don't sleep at night?

[Asaaaan]

When you don't have to get up at a certain time can you then sleep in later?  For example, on the weekend do you sleep from 3 AM to noon?  If so, it sounds to me like you may have Delayed Sleep Phase Syndrome.  Essentially what that means is your body's biological clock naturally is offset by a number of hours, so you'll naturally fall asleep very late and wake up very late.  

See this link for more details: http://en.wikipedia.org/wiki/Delayed_sleep_phase_syndrome

[margypops]

I have found several things keep me awake, I start to dwell on problems when its quiet and no distractions ie TV,  also any caffeine after Noon, its still in your Body and for me I have just found out Sugar substitutes keep me awake and give me morning headaches,.It also depends how old you are how much sleep you need, 6 hours enough if you are 50 or older maybe 7-8 if you are younger. If you go to work at 4-30am or so I assume you finish work early are you napping when you get home,that will make you go to sleep later.I still battle it but it gets better I get some good nights some Bad nights I kind of accept it now.

[Naominjw]

Perhaps your brain/endocrine system is not producing the proper chemicals in the proper diurnal cycle to sleep properly. This can be that way from birth.  Now if you ask WHY are those chemicals off... your guess is as good as mine.

Have you had a sleep study done? What about cortisol levels at night and in the morning? Both of these were abnormal when my daughter had these tests. So were other hormone levels indicating hypothalamic-pituitary involvement.  

Help for her came multi-dimensionally with melatonin, herbs, dietary changes to address food sensitivities, medications, and addressing hormonal deficiencies. However, I, too, am still searching for better ways to help her, and for deeper understanding of "why?"

Sleep is so critical. I wish you the best.