Okay, I can only share my own experience. I am bipolar. I started taking Zoloft some months ago (200mg). I was slammed with the most worst angst/agitation/mixed state AWFUL mood issues imaginable. My p-doc said he believed the Zoloft was causing me to have "negative mixed-state hypomania". I dropped the dosage and immediately felt better. I'm now down to 25mg Zoloft and the positive change in my moods is remarkable. I plan on going off Zoloft altogether. Oh - also, I have seen a number of threads on PC about Zoloft setting off negative manias for people who are bipolar.