Modafanil is advertised for alertness and from my experience seemed selective. No jitters, no palpatations, and most interestingly, did not significantly act on sleep receptors. This creates a peculiar dynamic though when tired, as sleepiness combined with alertness gives a headache-y tension.
Onset is also fairly slow, taking a few hours to really set in. This can be shortened by crushing the pills. The effect lasts a surprisingly long time, around 12 hours or so on 300mg, and there seems a build-up effect after a few days. After 3 days I can even skip a day and still feel somewhat influenced. I used modafanil for about a week, and over time there are more noticable effects on sleepiness and sleep.
I didn't find Modafanil to have direct appetite or psychomimetic effects like amphetamines, although the highened focus of the drug resulted in eating less and a little mental instability. As anyone knows, even sleep deprivation can cause psychosis, and the stimulating effect of modafanil seems to bring the whispers from beyond a little closer. I'm surprised actually that people can take this drug for long periods without more untoward effects.
For me, it was useful for the intense focus I required at the time. Its not anything I'd want to take for long periods. There isn't any euphoria.
