Treatment would depend on what symptoms you are having.
Not sure why you aren't having a colonoscopy. Sounds like you may have ulcerative colitis limited to left side of colon or proctosigmoiditis. You may want to try probiotics, or ask your doctor for prednisone, Mesalamine rectal enema, plus possibly Flagyl and levaquin, (levofloxacin) depending on the degree of suspicion for ibd vs possible infectious causes.
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