Yeah, they work for as long as five years, after which their effectiveness begins to dissipate. And when you want to withdraw, you'll go through pure hell. My recommendation for anyone contemplating use of an antipressant is to NOT use any SSRI and/or SNRI meds. Physicians do not warn their patients that withdrawal from SSRI/SNRI meds is very unpleasant and has diminishing quality-of-life residual effects.

And make sure you're talking to a doctor who knows what the hell he's talking about when discussing antidepressants. Most general practioners (including internists) prescribe antidepressants much too cavalierly, including for menopause, for instance.