When getting chemo I had a severe GI reaction each time/ it appeared as if the intestinal lining came out. Sorry, sounds gross.
About 15 years later I started having autoimmune GI illness. Initially microscopic colitis and later hard to diagnose GI symptoms that also caused intense fatigue. Short term steroids would make me feel great. I was seen at Mayo at the time. Eventually, there was new discovery that people like me in addition to people with abdominal trauma could develop this non specific type of GI inflammation. I even developed Sjogren like symptoms affecting mouth and eyes.
I was offered immunosuppressant treatment. I took this medication for 7 months- my symptoms disappeared.
There were brief milder flare ups later on- I’m fine now.
Remember- this was a very rare occurrence!