Try sublingual, transdermal, injectible, or IV supplements. If you've got a gut problem, you probably have malabsorption issues, making your problems worse.
Can you get any amino acids down? Glutamine is given to cancer patients to help rebuild the gut lining from from the harshness of chemo - 5-15g a day is suggested. Glycine can be very helpful, too. There's also Great Lakes bovine gelatin powder which has a good mix of aminos that's pretty easy to get down.
Next you could try probiotics, like Thorne Fiber Mend and Seeking Health GOS (galactoligosaccharides) powder.
Thorne PermaClear might be a good start for probiotics. It contains glutamine to rebuild, quercetin and ginger to soothe your intestines and a couple of easier strains.
Then, there's HLC/Pharmax human strain probiotics which is good.
Then Xymogen ProBioMax 30DF, then 100 as you can tolerate it.
I rebuilt my gut after chemotherapy with the above.
Later, you could look into other strains, like Prescript Assist.
Best of luck...