Mirtazapine
"I think this drug (15mg) significantly helped me with my insomnia initially. But I don't think it did anything for me beyond the first couple of weeks, as my insomnia began to rebound. I think this is a good SHORT-term drug; I would resist the temptation to take it for longer periods for the treatment of insomnia, since most of its sedation effects wear off within weeks (as with all sedatives)."