narcolepsy
"I took Provigil for 6 months with varying doses (100-300mg/day). It only took about 20-30 minutes to kick in and lasted roughly 7 hours. It gave me an incredibly high level of alertness. I also have mild cataplexy and sleep paralyzation, and it seemed to help keep both of these under control. However, it also gave me very bad nausea and an even worse headache. When the medicine wore off, my body reacted by immediately having a strong "sleep attack". If I didn't take my next dose before the first had worn off, the second didn't seem to work. Also, my urine smelled strange and the smell got even stronger when I drank more water. This stopped as soon as I changed my medication to Adderall."