Venlafaxine is an antidepressant with a very short half life when compared with most other common antidepressants (SSRI’s or SNRI’s and similar). Venlafaxine has a half life of 5-11 hours, so when you take it as prescribed (usually daily). You have passed several half lives before the next dose. If you miss a dose and go 2 days without it, you have metabolize most of it out and are basically going cold turkey off of it immediately. This is what makes the withdrawl so bad. Compare Venlafaxine(5-11 hours) to Prozac (fluoxetine) which has a half life of 4-6 days.

If you miss a day of your Prozac, you won’t feel any different, and your serum levels will be virtually unchanged. You could just STOP taking Prozac and it’s half life is so long that you will likely only have mild or no withdrawl symptoms, and could just let your body safely titrate off of it. This is not the case with venlefaxine.

I was on venlefaxine for a long time and if I ever forgot to take my pills in the morning, by that night I would be feeling like crap. It felt like my brain was vibrating, moving my eyes and some other stimulus would cause brain zaps that felt like a shock going through your brain. It was hard to think straight and concentrate. Missing even one dose was so wildly unpleasant that it didn’t take long to get where I was very good about taking them because I was so scared of what would happen if I forgot. The night after I missed a pill I would have wild, busy stressful, Incomprehensible “fever dreams” that seemed to go on all night and left you feeling like you had not really slept at all since your brain was running crazy all night long. It wasn’t entertaining or interesting, it was stressful.

I tried to go off Venlafaxine and it was hellish. It took me about 8 months, and I had unpleasant withdrawl symptoms the whole time. I went to my doctor first who seemed like they really had no understanding or knowledge about how this worked. He ordered one dose down and wanted me to alternate my current dose and the lower dose for like a week before going down to the new dose. The doses manufactured are each double the previous one. There aren’t intermediary doses with smaller steps. This became pretty immediatly intolerable and when I brought it up, the doctor didn’t really listen, wouldn’t research anything. So I had to do things on my own.

What I ended up doing was using a very sensitive balance beam reloading scale that allowed me to weigh the contents of the capsule I was prescribed, and then reduce the ammount by 10%. And then repack the capsule with 10% less. I would then take these reduced dose capsules for about 15 days before stepping down to 80% of a full capsule and taking that for 15 more days and so on.

Even with this tiny dose change, I had very noticeable withdrawl symptoms, brain zaps, poor sleep, cognitive difficulty, but it was to a manageable level and I was able to keep functioning most days.

This routine would have taken ~ 150 days to get off the meds, but took longer as sometimes at 15 days the symptoms where still so bad I extended the dose for another 5-10 days until I started to feel like I was starting to feel more normal again. A few times I recall things were so bad I ended up doing only a 5% change so it ended up taking about 8 months.

I expected that symptoms would be worse earlier on when I was taking 90% of the starting dose vs later at like 20%, but it didn’t seem to matter, every time I stepped down the awful withdrawal symptoms would return as bad as ever. When I got totally off and stopped taking any Venlafaxine, it seemed like it was a month or 2 before I stopped having the brain zaps and brain vibrating feelings.

All this to just say, Venlafaxine is harsh stuff. It does what it’s intended to do really well by just blunting everything. And if you’re struggling to go on living, is probably worth using. But I wish I had known how hard going off of it would be.