I knew it all looked exactly like
serotonin syndrome/
serotonin toxicity, so I called my doctor who advised I stop taking my Effexor, but I couldn't sleep for days and I got so bad that I had to go to the ER before I could get to my appointment with her. I was, indeed, diagnosed with serotonin syndrome, much to the shock of the doctor on call who diagnosed me. He'd never seen a case like mine, but there it was.