Can IBS develop suddenly? I recently just got up cramping terrible and thought I needed to go to bathroom but it was just "cramping". Went to the doctor and he immediately made arrangements for a colonoscopy which showed everything to be normal...however my "cramping" continues to come in cycles and usually wakes me up around 4:00 am. I am taking an anti-spasm drug called Dyclomine which helps only a little. The pain just about drives you crazy sometimes. I have NEVER had problems that were "bowel-related" before and was just wondering if it does occur this suddenly. It has been several weeks ... some days being better than others. What are the foods to avoid the most? Waiting for your replies.