"i have been on effexor xr for 17 years now. i take 150mg once a day. my biggest negative side effect is extreme, excessive  sweating. i tried going off it earlier this year because i was fed up with this issue and thinking that maybe i really didn&#039;t need  it any longer. bad mistake. within 2 month&#039;s i was back at my doctors a mental mess and was put back on it. i guess you have to take the good with the bad. does anyone else have a issue like this while taking this med? it can be very embarrassing and makes me very self conscious."