Modafinil(provigil) and Nuvigil are very similar. The difference is that Nuvigil is missing an insomer that provigil has so its sort of like half-provigil. My husband used to take it for narcolepsy. They used to recommend it for adhd but then the company was sued after 1 person(child ) died of something called Stevenson Johnson syndrome-accept that was debunked years ago but they were hurt enough not to allow anymore off label recommendations. There are some promising studies being done on the use of provigil as an off label antidepressant for people that have treatment resistant depressions and some really promising studies on the use of provigil in the treatment of Parkinsons and Alzheimers.