Hi welcome to Health care magic forum.
Thanks for calling H.C.M.F.
As you describe you are going to have colonoscopy
, and possible diagnosis could be chrons disease, or ulcerative colitis
. You want some remission in the mean time .
I advise you to avoide spices, junk foods, and oily foods to prevent irritation of the gut, and hence motility.
Take bland foods as far as possible, in small amounts at a time and more times. Take more of water.
You can take antacid
liquids for soothing the gut.
Wishing for a quick recovery .