I have just been swapped from fluoxetine to venlafaxine. Today is day 2. Starting with 37.5 for a week then 75 the next week. I stupidly googled it and came across all the horror stories. I am worried about the change as I swapped from fluoxetine to sertraline about a year and a half ago and ended up going back on fluoxetine. Looking back I don't think I gave it enough time and it was maybe a combination of the fluoxetine wearing off and the new med not yet working but I felt awful.