I had the same problem and realized it was the Splenda. When I started using it, I ended up in the bathroom almost all day with nausea (and other problems) for a week until I finally figured out the problem. Splenda just doesn't agree with me, and I'm quite sorry about that, because I really LIKED it. Hopefully, that will not be the problem for you, but if you're using it, you might consider stopping and seeing if you improve.

Good luck.

Mary H.