"brand name lunesta works like a charm. i get 8-10 hours of sleep a night. i have never built up a tolerance and i have never had episodes where i did not remember things if i didn&#039;t go to bed right away. i have fibromyalgia and rem sleep is very important. last month i got the generic brand and i haven&#039;t had a good nights sleep since. i can&#039;t fall asleep at all. if i start to drift off my brain suddenly wakes up. i&#039;m not even getting 2 hours of sleep a night and that is after laying there till it&#039;s almost time to get up and i take 2 muscle relaxers to get a little sleep. now my pain is unbearable."