Lamotrigine
"After 10 years of having nearly every SSRI' and SNRI work and then fail, I developed Sertonin Syndrome on a cocktail of both. I was so afraid to try any antidepressant...but my depression became life-threatening.  I'm on only 50 mg. of lamictal (going slow!) for a month...and I am becoming cheerful!  Amazing.  I do have a slight facial rash I'm carefully watching.  No other side effects."