depression
"I was 1st prescribed Zoloft, which for me was absolutely perfect until none of my clothes fit about 3 months into it.  I gained 25 lbs and the weight gain brought new depression and anxiety.  I was put on Wellbutrin which was a "nice" drug if your depression isn't too severe and I lost weight on the it, but it couldn't hold a candle to my problems.  Then, I tried Pristiq (and I also use Valium and Ambien for any additional anxiety).  It's a happy medium between the 2 medicines.  You won't have the side effects of Zoloft (weight gain, loss of sexual interest), but you'll have a stronger backing against the physical and mental toll of depression and anxiety.  "