This article is mostly about this writer’s attempt to get off of Effexor but does mention Paxil fleetingly once or twice.In their studies, Rosenbaum and Fava found that Paxil and Zoloft, with half-lives of one day, proved more difficult to get off than Prozac, with a half-life of four to six days. Effexor, the drug I was on, has the shortest half-life of all: five or six hours.
http://www.nytimes.com/2007/05/06/magazine/06antidepressant-t.html?ref=magazine