ABC News recently did a story about off-label use of Provigil, a stimulant that is approved by the FDA to improve sleepiness in narcolepsy, obstructive sleep apnea, and shift work disorder. Apparently, there is an increasing number of Americans who are taking Provigil, and the article implies that it is being taking for off-label reasons - to improve focus and daytime energy. The article talks about a few people, most of who remain anonymous. They all tout the benefits of taking Provigil. It's not stated whether these individuals have been diagnosed with a sleep disorder or if they received their prescriptions from their doctor or online.
ABC News did an "experiment" on one person - a software company CEO who takes Provigil daily. They had him stop the Provigil for 3 days. He noticed a "very slight" change in his own speech, whatever that means. They had him do cognitive tests off the Provigil. The next day, he took the Provigil, and reports feeling more alert in 17 minutes. This is implausible, as it most likely had not even been absorbed into his bloodstream yet - this makes me think there is a significant placebo effect at work here. After he took the Provigil, he repeated the same cognitive tests and reportedly did much better. ABC News implies the Provigil is what helped - but could he have done better just because he was repeating tests he had taken the day before? In other words, he may have improved due to learning what to expect from the test, not from taking Provigil.
Taking Provigil off-label could be dangerous. Recently, a life-threatening rash has been reported in some taking Provigil. Not discussed in the article is that Provigil, and it's new brother Nuvigil, may reduce the effectiveness of oral contraceptives, making unwanted pregnancy more likely. Finally, the article mentions that there are no studies showing that performance improves with Provigil. In fact, if you take Provigil to offset sleep deprivation, there is a good chance that you will not gain much, as sleep loss itself reduces performance. I wonder how much placebo effect the people in the article are receiving, as they all think they are taking "Viagra for the brain" as stated in the article.
Instead of taking Provigil to give yourself a theoretical edge, it would be better to eat right, exercise daily, get enough sleep, and prepare better for whatever life brings your way.