narcolepsy
"I have narcolepsy which went undiagnosed for decades. I don't drink coffee and for years self medicated using caffeine tablets and diet sodas. Finally in desperation started looking for answers via the net, had a sleep study and voila, narcolepsy. Tried Ritalin with no effect, then Provigil and for the first time felt normal and productive. Health insurance would not cover and soon I was paying $800.00 a month for meds. To make matters worse, the Provigil soon lost any efficacy. Ultimately my Doc, reluctantly prescribed Adderall and I have been taking 30mg in the AM and 20 more around lunch. This works ok, but still need caffeine."