anxiety and stress
"I have only been on it a couple of days, but the side effects are terrible.  I am prone to insomnia, and this exacerbates it terribly.  Even with 10mg of Ambien at bedtime, I am only getting 3.5 hours of sleep.   I am also having muscle shakes, mostly at night.  I'm having daytime muscle twitching that causes me to be very uncoordinated and drop things.  Last night while I was trying to sleep I saw strange geometric patterns, and when I would get close to actually falling asleep I would see a bright flash of light and hear a booming noise which would wake me back up again.  Considering all of that I am able to function pretty well in the day time.  Also: constipation..."