depression
"I have suffered from severe anxiety and depression since 2002 when I had cancer and did chemo.  The chemotherapy I did saved my life but it messed up my hormones so much that I went into premenopause at the age of 17.  I have been on various doses of Effexor XR for the last 8 years ranging from 75-300mg a day.  I needed medication to live a normal life.  In the last year or two, I had been progressively getting worse until I felt like I was spiraling out of control.  I had been working with my doctor to find a solution but nothing was working.  Extra meds were not helping.
Desperate, I tried niacin.  500mg a day.  Flushing is worth it.  I am now off Effexor, and on niacin instead and it works better with less side effects, only the flush."