I guess you might call your doctor, but since the effexor is an antidepressant, I would think that not having the chemical anymore could cause you to feel depressed. That's why I can't imagine that I will ever be able to quit my meds, but then for me depression was my primary diagnosis.
"It's a jungle out there....."
Theme song from "Monk" by Randy Newman
"Turn this car around... I'm goin' back..."