I have been taking serequel for more than 10 years now & carbamazapine at bedtime.& I am bi-polar.But these two combos worked very well for me for years now.I went to dr, today And he wants to try trazodone Instead of serequel.Is there any time That it will take for me to know it works better or not.he said he would change it back if I had problems.and also how long does it take to work for sleep once you take it.? for w/serequel it took 1.5 hrs.I just want to know what I need to before I start it.any imfo will help.Thanks.