From Erowid:
Some drugs also interfere with cyp2d6. Prime among these are the SSRIs, with the exception of Zoloft (if I remember correctly). The most potent inhibitor is paroxetine (paxil), followed by fluoxetine (prozac). If you are taking an SSRI, you will probably experience a markedly decreased euphoria when using codeine. (Paxil has a half life of only 24hrs, so not taking it for a few days will do miracles; the half life of prozac is 7 days.)
I know that SSRIs (aropax, paxil, paroxetine) lesses the effects of codeine. Does anyone have any personal experience with this combo? How much are the effects reduced? Is the combo dangerous?