"i had a very negative experience with this drug.  i had been on effexor xr for years. my doctor suggested switching to pristiq which was supposed to be the replacement for effexor when the patent ran out. i immediately had horrible migraines, agitation, uncontrollable feelings of anger. i called the doctor&#039;s office on the third day and was immediately taken off the drug. they said i was not the first person with those symptoms.  "