Does anyone have sleep attacks while on modafinil? Hi everyone! Thanks for the add. Just got diagnosed about a month ago with narcolepsy w/o cataplexy. Doctor put me on modafinil. I started with 200mg daily. It worked for about a week then by week 2 I started getting sleep attacks in the afternoon again. He upped it to 300mg. Same thing, worked for a week, now I'm back to having sleepiness/ feeling spaced out. Should I give it more time? Or does this sometimes just not work for certain people?