<<Disclaimer: Verify this information before applying it to your situation.>> For a long time I've suspected the coffee at work. A few years ago I'd identified the sugar bowl as a culprit. Then we moved buildings (and coffee suppliers) and I started getting problems again. Sugar and creamers are in separate packets. 3 week vacation and I was fine until I went back to work again. After a few weeks I cut out coffee at work - but I still drink coffee at restaurants and sometimes at home, with no problems. SO.... What could the problem be at work? The bland coffee? The coffee filters? Just drinking coffee regularly instead of tea? I'm running out of ideas. Stuart