obstructive sleep apnea/hypopnea syndrome
"My problem was falling asleep while driving and falling asleep in class at nursing school. My doctor prescribed Provigil at 200mg in the morning. The first day was
simply incredible.  After that it didn't seem to work anymore. So the dosage was raised to 300mg.  Same affect. So now I take 400mg only on the days when I have class.  That seems to be enough to keep me going on the other days too.  Provigil is a very good medicine, and I am blessed enough to have insurance that pays every penny so I am not aware of the price. (And I still have to make sure I get at least six hours of sleep at night.)"