Hi Jennifer

This is a good question to ask of your doctor.  But I can do some research in the meantime for you.

On this web site which discusses PMDD, they give a list of anti-depressants which have been researched for this purpose:  "Fluoxetine (Sarafem), paroxetine controlled-release (Paxil CR), and sertraline (Zoloft) are FDA-approved for both continuous and intermittent use. Which approach is best varies from woman to woman and is best determined with your physician or nurse practitioner. Some other antidepressants (e.g., citalopram [Celexa], clomipramine [Anafranil], escitalopram [Lexapro], mirtazapine [Remeron], venlafaxine [Effexor]) show promise for treating PMDD, but they have not been as well studied as the SSRIs and none of them are FDA-approved for PMDD."

From a previous article I have written about antidepressants and weight gain...it seems that both Paxil and Zoloft can cause some people to gain weight.  Perhaps using these intermittantly, however, may not cause you to gain weight.  You really won't know until you try the drug.  Everyone reacts differently. 

An article in American Family Physician also discusses which medications you can use to treat PMDD: "Serotoninergic antidepressants such as fluoxetine, citalopram, sertraline, and clomipramine are effective when used intermittently during the luteal phase of the menstrual cycle."

Read my article about which antidepressants are least likely to cause weight gain...which you may find here.  I believe Celexa is on that list.

But again...do discuss your options with your doctor.  I wish you the best of luck in making your choice.