narcolepsy
"After a few years of being diagnosed with narcolepsy and excessive daytime sleepiness, someone I knew who had narcolepsy as well recommended I ask my doctor about Xyrem. I am glad I did because about a week after taking it I started feeling normal again. 
I still have some "bad" days,  but they are better than my best days prior to taking Xyrem. 
The only thing I don't like is their list of side effects being unclear. I have had stomach issues, loss of appetite, and significant weight loss. I was beginning to think something was wrong with me because these are not side effects listed on their website. It wasn't until I stated searching other forums that I am finding others having these same types of symptoms."