They have the same active metobolite (which is thought
to have the beneficial effects) but
Pristiq has succinate salt added
to it which allows for a predictable concentration of the medication. What all this means is that most patients will be able to stay at the starting dose of 50 mg with very good results. There have been very low incidences of side effects, little to no weight gain and sexual side effecfts don't seem to be an issue either.