Collywobbles

To have the collywobbles means to suffer from an upset stomach (though the Oxford Dictionary describes it more specifically as pain or looseness in the bowels). It’s a colloquial term and was first recorded in 1841.
 

I love the word collywobbles.  It’s one I used to hear quite often when I was young but nowadays it isn’t generally considered sophisticated enough.  I hope it doesn’t die out completely.