What should I expect when mom has "colonoscopy' in couple weeks?

I have been caring for mom who has dementia for two years, and now other health issues are coming to surface. She is anemic, and so they want her to have colonostopacy test.(no idea how to spell that word) Her consult doc. said she may have internal bleeding. If she does, I wonder what can be done about that? Is their any OTC meds or supplements that could help with her gastric system? Just really scared on what they may find. He said it could be several things. If any one knows anything about this I'd like to hear what to expect. Thanks so much!! All of you on this site are just wonderful folks to converse with and ask advice from. So grateful for Agingcare.com.