I have really bad PMS as well, and have been diagnosed with PMDD (Pre-Menstrual Dysphoric Disorder). Before I was diagnosed, I would PMS for 2 weeks, be really physically sick the week of my period, and then have one week to recoup. It sucked, and I was originally put on Zoloft to help it.

The Zoloft started to work, but then my body grew a tolerance to it...so I had to up the dosage, and between that time and the time when I gave up on the Zoloft I gained about 40lbs.

So, in talking with my doctor, I was prescribed Lexapro. There are a couple of other threads in here on that particular med, and it has mostly rave reviews. I tried low-carb the first time on Zoloft, and nothing happened, but Lexapro has no effect on my weight loss. The best part about Lexapro is that you don't need to take a lot of it to have an effect (I take 10mg a day).

To answer your question about food cravings, I always had them around PMS time on the Zoloft, but the Lexapro has squashed my major food cravings. I may have one or two nights before my period where I have cravings, but other than that I am fine

Hope this helps!