I was initially diagnosed with a Major Depressive Disorder; my first round of SSRIs sent me into a manic episode. That was enough to get me diagnosed with Bipolar II. I question whether that was an accurate diagnosis; my experience with bipolar medication was pretty awful, and with behavioral treatments (CBT and environmental changes) I seem to do okay without them, which is much more rare for people who suffer from Bipolar than for people who suffer from MDD.