narcolepsy
"I started taking Xyrem about four weeks ago. It is very easy to take and since taking 4.5 g 2x/night, I know pretty accurately when I will wake up (midnight alarm is not needed). I am also taking Adderall 5-10 mg 2-3x/day and I no longer feel tired and am very focused during classes. Since taking Xyrem, even at the highest dose, the only adverse side effect I have had is nausea, if I don't go to sleep within 20 minutes after taking it. HIGHLY RECOMMENDED."