Hi Christian,
Yes, from what my psychiatrist and my own research has offered, provigil seems to be safe.
Luckily, I have perscription coverage because provigil IS extremely expensive and has not yet gone generic.
I take 100 mg. two or three times a day. The maximum dose is 400 mg a day, at least that's what my doc says.
It does help a lot with tiredness and grogginess, although I've found you can build up a tolerance to it. Then, I have to cut back for awhile. It is suggested you don't take a pill 8 hrs. prior to going to bed, but I have had to do that and it hasn't interfered with my sleep. Sounds like a wonder drug, doesn't it? The drawback, for myself anyway, is the tolerance I build up.
I don't know anything about it causing positive permanent effects in the brain, and my doc hasn't said anything about this. I will ask him when I see him in a month.
If you have any other questions, let me know. Also, let me know if you decide to go on it.
Take care.
Carol