Provigil is the only reason I'm still able to work full time. I have 100 mg tabs which I cut in half. I take 50 mg at lunch and if I'm still dragging, I take the other half.

For me it will lose its effectiveness if I'm having a bad time with fatigue and take it on a regular basis. I always skip weekends to give my body a break.

You might ask your doc if he has any samples you could try. It's expensive - $50 co-pay with my insurance - but oh so worth it.