What Should I Eat Or Take After A Severe Lower GI Bleed With No Cause Found On Colonoscopy?

I had a lower gi bleed, I almost died, Nothing showed up on colonoscopy. Had about 6-8 bags of blood. Released from hospital, after 4 days. Ok to go back to work. 65 years old, confused on what to eat, and any meds to take. If any ! Nothing suggested by Hospital Staff