Doxepin
"I have been taking Silenor every night for 5 months and love it.  It doesn't knock me out or make me loopy like Ambien.  Silenor just makes me a bit drowsy, but more importantly is that when I wake up in the middle of the night I fall right back to sleep - which is a lifesaver for me. Since it's non-addictive, this is great for just normal calm times in my life, which is 95% of the time.  But when I'm stressing out over something and all panicky, then Silenor does practically nothing for me.  I have to take Ambien or Ativan during that 1-2 week period I'm stressing."