sedation
"I developed insomnia for the first time several months ago, and other medications such as Ambien, Lunesta, and Restoril were ineffective (I would wake up 3-4 hours later).  Hydroxyzine has worked beautifully.  I sleep until my alarm goes off, but wake up feeling rested.  Like others on this forum, I've found it promotes a very vivid dream state.  I believe the medication promotes REM sleep.  This is probably a good thing, assuming the dreams are tolerable, as REM sleep supposedly enhances memory and learning.  The medication is also very inexpensive, which is a plus!"