To my knowledge there is no long term side effects to taking Ambien. I took it for two years I dont take it anymore. The risk is that you could become dependant on it some people decide to take more as they use it becuase they dont get to sleep right away anymore. Ambien works like a hypnotic so you should take it and go right to bed, sometimes you wont realize that you really are tired after you take it becuase you get into like a trance like state. Dont ever take more than the dose perscribed my your DR. that is where you get into trouble.
I am fine and I took it for a long time, there is a new drug on the market that works with the central nervous system of the brian and I am not that familiar with it nor do i dare try and spell it, but you can ask your Dr. about that.
There is a book that helped me called "no more sleepless ngihts" read that, that will for usre put you to sleep