My bad - it seems that I didn't do my research well enough. When I googled it (is googled a word?), this showed up as the #1 hit. When you go to the page referenced it's actually showing the roots of dyspepsia dys-pepsis-ia with pepsis being digestion...
Perhaps I have been confused by problems I have had with my gut which may have been where I heard (or misheard) the term.
Sorry, I withdraw my request.