I imagine the swelling you have is of course because your guts are full, and as the waste breaks down, it'll give off gas
. An alka seltzer will help get the gas
out of your stomach, and it'll also make you feel more comfortable.
The only other thing I can think of about shingles is it does cause a paralysis of some kind... could be if it's near your abdomen, and once the shingles goes away, your digestion will improve, but I am not an expert on all that stuff.