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.

I can also confirm brain zaps both when I tapered down and if I missed a dose. It was unpleasant but I put up with it when reducing my dose. I changed from it because it caused insomnia as a side effect badly enough that it was worse than the problem.

My understanding (which may be incorrect, not a doctor) is that you need a higher dose to achieve the N part of the SNRI. I wonder if this somehow linked to the experience. On lower doses of SSRIs I never had any such experiences.

I would guess it has more to do with the serotonin, Atomoxetine has small S activity and large N activity and relatively it can be discontinued much easier than any of these other drugs.

That's what I thought as well. On the medication I was on afterwards it only inhibited serotonin reuptake and the dose was lower. I imagine a really high dose would do the same thing as well.

I was on venlafaxine for about 5 years and had always heard horror stories about the withdrawals. About 7 or 8 months ago I decided to ask my doctor to start tapering me off. Took about two weeks in total and the only side effect I had was when I would turn my head I could "feel" my brain moving around. It was a very strange sensation. I was on 150mg and then 75mg to nothing. I feel extremely fortunate I didn't have any of the issues most seem to have getting off the stuff.

This gives me hope

Another hopeful story for you: I was on 75mg, abruptly stopped a few months in, mostly smooth except for an occasional mild brain zap, and those stopped after a couple months.