I'm not sure why one would combine the two, only because they're pretty similar drugs. That's not to say one wouldn't benefit from it; I really don't know medication that well. I've been on both Paxil and Cymbalta (Effexor's cousin), but not simultaneously. I find that Paxil works better, for me.
If I cannot forgive myself for all the blunders
That I have made over the years,
Then how can I proceed?
How can I ever dream perfection-dreams?
Move, I must, forward.
Fly, I must, upward.
Dive, I must, inward,
To be once more
What I truly am
And shall forever remain.