narcolepsy
"I love this medicine! I am pretty young and had never had to take medicine before, my doctor started me on Nuvigil but it gives me a headache every day. After a month he started me on Xyrem. At first it was too low a dose (1.5 grams) and I felt like I hadn't slept at all but then he upped it to 3 grams and I don't even have to take the Nuvigil anymore. I can get 8 hours and stay awake all day, I do get pretty sleepy after eating but that is nothing compared to not having any kind of medications to help. I do feel sick if I wake up too early, or if I wake up on time it takes an hour before I can stomach food."