Aricept - side effects?

Hi. I started Aricept about a month ago at 5mg & upped it to 10mg about 1 1/2 wks. ago. I'm having a horrible time with sleep, even taking some kind of sleep aid (which I am against but am desperate now), & it helps minimally. I am also nauseous on & off all day which may be b/c of major lack of sleep. I'm supposed to take the Aricept at bedtime but have just started taking it earlier in the day. I'm hoping that if I take it in the morning, the sleep trouble will go away. I would so much appreciate any feedback anyone has to offer. I truly believe this med. helps or I would have stopped it a few wks. ago. Thanks! Rondi