I've had that happen to me several times while taking Ambien. My first "Ambien hallucination" (if you want to call it that) involved the uncontrollable shaking--which was akin to the restlessness of akathisia-- and visual distortions. For example, I thought my cat's face was melting, kind of like the scene in the first Christopher Nolan Batman movie where Batman's face mask is melting when the doctor is dosed with a taste of his own medicine. Sometimes I also experience auditory distortions which then make me paranoid and I stay up wondering if I heard what I did or not.

The first time is jarring but then you just recognize when it's happening and know that you have to force yourself to close your eyes and go to sleep. Like another poster suggested, the way to avoid this side effect is to immediately go to sleep right after you take Ambien. Alternatively, don't take Ambien. In my experience, it's a very habit forming drug and it's difficult to stop taking it because your body eventually will not sleep without it.