narcolepsy
"This medicine is doing it's job.  I actually fell asleep standing up in my dining room.  Hit my chin on the table (ouch). Now, I don't fall asleep at inappropriate times (after I take my  first dose). I do have concerns about it's habitual possibilities, which I must say, my doctor did not warn me about. I will have to keep a close watch on my behavior I guess, but it is working."