Twice in one month I have suffered severe diarrhea--gurgling intestines and completely liquid stool, each time lasting 1 to 2 hours. I'm VERY frightened at having suffered two bouts over such a short period of time. And here's my history: I have had IBS for 40+ years that underwent a change about 6 years ago, when while walking I felt a sudden searing pain in the lower right abdominal quadrant that literally stopped me in my tracks--a pain that has recurred periodically since then. I also had never suffered from severe diarrhea until 4 years ago, when out of the blue I awoke one morning to the urge to evacuate my bowels and had completely liquid stool--3 bouts over a period of about an hour. I wrote it off as an anomaly, but when it happened again 6 months later (again in the morning) I made the connection that both times I had eaten catered food, so I wondered if they contained a preservative to which I was (or had become) allergic. Even the third time it happened, another 8 months later, it was after I had eaten some foods at a catered event. But when it happened two more times--each about 6 months apart--I couldn't attribute it to catered food. About a year ago my IBS also worsened (pain and recurring loose stools) and in late 2013 I had a full abdominal scan and then a colonoscopy in July 2014, which revealed that I have moderate diverticulosis and internal hemorrhoids and that my large intestine is rigid/twisted in parts--to such an extent that my gastroenterologist has concluded that I'll require virtual colonoscopies in the future. One thing that might be helpful in diagnosis/treatment: I sometimes feel full very shortly after eating, and last night I felt that and a stomach ache before going to bed...followed this morning by the severe diarrhea. HELP!