I echo your experience. Effexor/Venlafaxine are absolute poison. I tapered off of it slowly over the last two months under doctor’s supervision. The day after I took my last dose — small thanks to the tapering — I’ve had constant brain zaps, wobbly vision, horrible perpetual nausea, cold sweats, and inability to sleep more than an hour at a time. It’s been two weeks so far of lying in a dark quiet room waiting for things to resolve so I can go back to my wife/kids/job/life. Still no noticeable improvement. On sick leave for the first time in my life.