depression
"Effexor XR has saved my life twice.  The side effect was major weight gain, but, sad as that was, it was worth it after trying several other drugs that did not work.  The withdrawal is tough, but done easily if you just keep reducing your dose.  The first time I went off of it was cause it was making me depressed again, even at the smallest does.  But, 3 or 4 years later, when I once again sunk into a deep depression, it was the only thing that could get me out.  I've been on 150 mg one year."