I don't know anything about Cymbalta but a lot of the depression type medicines have a time to get used to them. So you might be sleepy at first but your body just has to get usd to it. I guess I should add that many meds are given for uses not originally intended for. The first med my neuro tried on me for my fatigue was Prozac. I wasn't depressed, it was just a proven fact that it helped fatigue. I have tried a lot of meds for it and we eventually settled of Ritalin.