Hi. Thanks for your query. Noted the history of horrible constant pain in abdomen, on sides and lower abdomen and under ribs, watery stools then constipation, mucus in stool in spite of normal colonoscopy. Also a known hypothyroid. Wants to know the reasons. The better part is that your CT scan and Colonoscopy are normal hence the cancer of the colon is ruled out. The problem then looks to be due to entero-colitis, the excessive mucus production and the watery diarrhea are indicative of either an infection or intolerance. I would advise you the following in such a situation: Get the stool tests done and also the tests of blood, particularly for CBC and thyroid status. Get a course of an antibiotic, metronidazole and probiotics and this may solve your problems. Also add on activated charcoal and multivitamins. Also take a note of the foods and beverages that cause the intestinal problems and stop them altogether.