Generally nonaddictive (no worse than ritalin or adderall); prescribed for narcolepsy but also used off-label for ADD, with results comparable to ritalin or adderall. Works on dopamine in a different way than ritalin or adderall, and doesn't have as dramatic drop-off side effects as those two when it wears off. There is a new forumalation - nuvigil - that appears to have a longer effective time for each dose.