narcolepsy
"I was diagnosed with narcolepsy in 1998.  I have been on Cylert, amitriptyline, Ritalin, ambien, and now Provigil.  The Provigil is a life saver. I did lose weight on it at first, but have leveled off and have not lost any weight since then. I have taken Provigil for 2 years now.  It is not an "upper" and does not make me feel drugged.  I take 200 mg in the morning.  It does not wake me up, it helps me maintain the wakefulness that I need to get through the day. Without Provigil, I would not have a normal life. I am thankful to have found this drug.  I would, however, like a generic to it that would help to offset the exorbitant cost of the drug."