narcolepsy
"I have taken Provigil off and on since 2000, for narcolepsy/apnea. I started with the 200mg per day, but discovered that my brain required more. Since increasing my dosage to 400mg per day, I have fewer daytime sleep concerns. I have not experienced any appetite changes, and have certainly not lost any weight. This medication allows me to function, just enough to keep my job, and have a somewhat normal social life. No matter what dosage I take, my brain/body will shut down at approximately 6:00pm, and on the days I don’t take the medication; I pretty much sleep all day. I’ve made life style changes, such as, eating better, increased cardio, and strength training; just as a supplement to the medication and CPAP therapy. "