In the last month, I have had three episodes of what feels like stomach flu, yet it s come at very specific intervals -- every two weeks -- with almost identical symptoms. I start to sweat a lot, like an epic hot flash (I am early-postmenopausal at age 45, but I ve been on hormone-replacement for three years); then, sometime between 2 am and dawn, I m awakened with a very intense nausea. Then, for a few hours, I vomit and have diarrhea at the same time, and it s very painful and intense -- and afterwards am pretty much confined to bed for most of the day with stomach cramps that gradually subside. I m weak the day after, and usually feel more or less recovered by day three. I can t think of anything I m eating or drinking that is common to all three episodes. The first time, my little boy felt sick as well. But the last two times, it doesn t seem to be contagious. ... It s the frequency of the episodes that bother me ... that and how exactly the same they seem each time. .. thank you.